Summary:
This saw goes thru large diameter wood fast. Its production capacity is unprecedented.

Strengths:
Awesome power and performance. Durable well built quality worth the price of ~$1K.

Weaknesses:
None.

Summary:
would not buy anything else again

Strengths:
POWER! wow best power to weight ratio on the market, great saw for everything

Weaknesses:
a tad heavy after running one for 8 hours

Summary:
BAR NONE THE BEST BANG FOR YOUR BUCK CAN'T BE BEAT BY ANYTHING OTHER THAN IT'S BIG BROTHER THE MS880

Strengths:
WILL CUT ANY TREE YOU PUT IT AGAINST I RUN A 36" BAR ON MINE I TRULY THINK IT COULD HANDLE A BIGGER BAR AWESOME POWER AWESOME DESIGN VERY EFFICIENT FOR THE POWER YOU HAVE

Weaknesses:
STIHL DOESN'T MAKE A CASE TO PROCTECT THE INVESTMENT MADE

Summary:
Really a great saw that will handle anything you need to do.

Strengths:
Lots of power, it is truly the KING of saws. It is especially awesome with the duall port muffler cover that gives it a reported extra .5 to .8 HP.

Weaknesses:
None that I have found

Summary:
Best of the best

Strengths:
Absolutely love this saw,best running saw I ever owned.Run a 32 inch bar with 404 rapid super and it just eats the hardest woods.I use mine to slice the wood into pieces instead of splitting it,this saw cut dead black locust logs faster sideways than most saws cut cherry normally. Stihl is number one in my book.

Weaknesses:
noe

Summary:
Brilliant!

Strengths:
powerful

Weaknesses:
every one wants to borrow the darn thing!

Summary:
beats all saws any day even the boses 880

Strengths:
very powerful i love it i have a 32" bar

Weaknesses:
none at all

Summary:
Excellent saw, although I would not recommend as an only saw for anybody.

Strengths:
Very good saw for the larger timer, or for cutting larger stumps. Excellent power to weight ratio, good dollar value when you consider what you are getting.

Weaknesses:
A bit heavy for some users - if using all day. Consumes more fuel than the 441 or 361.

Summary:
Best, Greatest, Most Awesome, Super Star Quality, Work horse of a saw I have ever and will ever Own.

Strengths:
Pure Power, Immediate Throttle response, Super high Torque, Goes through Harwoods like a knife throough Butter, I love this saw

Weaknesses:
Couldn't really think of one.... No available Storage case?

Summary:
cant think of any better saw! they hwo think its to heavy is maby djust not man enough!,,,

Strengths:
i bought one allmost a year ago and i still havent found 1 thing to complain about,,, if its to heavy ill just have lift some more weights,jummy!

Weaknesses:
if any, the chain could run out of oil if youure cutting whith pushing chain insted of pulling, then i mean large wood!

Summary:
This is a professional use saw, made to be used everyday. Too much saw for the occasional use homeowner. I recommend this saw for the professional woodcutter. The saw does get heavy after several hours of use but it will not fatigue the user due to the anti-vibration. I found this saw to balance well with the 25" bar. Using a 36" bar makes the saw a little unwieldy but still very powerful. I have used a Husqvarna XP395 for a day of large pulp cutting and I have personally found the Stihl MS660 to be a superior chainsaw.

Strengths:
Robust. Very powerful. Balances well with the 25" bar. Excellent anti-vibe. Versatile saw using different length bars. Utterly reliable. Well built saw. Made for professional use; Retail price reflects it.

Weaknesses:
None found yet.

Summary:
Great saw, only running a 25" bar at the moment but thinking about purchasing a 36" for extreme cases, interested to see how it would handle the larger bar. Used for cutting jarrah, does so with ease.

Strengths:
Very powerfull, not too heavy considering the machine you get. Keep the chain sharp and nothing will stop it.

Weaknesses:
No carry case, Come on Stihl!!!

Summary:
if u can only afford one saw this one is it

Strengths:
best power to weight saw on the market,will not disapoint

Weaknesses:
NONE

Summary:
nice saw

Strengths:
almighty saw

Weaknesses:
none

Summary:
I'm the one who gave the Echo cs520 a bad review and said I was going to buy one of these. Well I did, and I'm not looking back. Very happy with the quality of the saw. Heavy and worth every sore muscle. Cost about $1100.00 out the door. A saw that can actually pull a 20" or larger bar as fast as you need it to. A pure joy to use for a woodsman. Wives, buy your husband one of these and he will marry you all over again!

Strengths:
Loads of power, a real honest-to-goodness pro saw that lives up to the Stihl reputation, Made in Germany. Compression release. Decent chain on the stock bar ( 25" 3/8 pitch .050 gage 84 drive links). I can cut hardwood all day as long as my arms and hands can hold out. Not really for average users, I suggest you have some cutting experience behind you before you spend the dollars on one of these. If you cut any moderate to large tree you NEED this saw! Put chisel chain or skip-tooth on it and just smile. It will rip through a 20" oak tree like nothing. Bucking the logs was like butter....

Weaknesses:
Needs the high-volume oiler as a stock feature, my standard oiler is maxed out and could use more oil, even during the summer months when the oil is thin, and this is on the stock 25" bar. Chain brake seems a little weak and the exhaust blows on it. For the money it should come with a fitted case and at least a spare chain! Injection molded cases are dirt cheap to manufacture (Are you listening Stihl??). Not crazy about the throttle going to warp 10 as soon as it fires up, this can't be good for a cold engine.

Summary:
Perfection with an orange case.

Strengths:
BAD ASS!!

Weaknesses:
tad heavy but you get use to it, and laugh when you hold a husqvarna!!

Summary:
Buy one, and hold on!!!

Strengths:
I have over 10 saws of many brands and my 660 is the only one I use. I switch between a 20 and a 32 inch bar for red oaks, and cut all day long. Never a disappointment. Being that its of official saw of the stihl timber sports, there are so many after market and stock parts readily available.

Weaknesses:
I hate the fact I cant bring it to the job or put it to rest every night in a plastic case!

Summary:
best power to weight ratio i`ve used to date

Strengths:
damn good saw lots of power

Weaknesses:
none

Summary:
I'm the one who gave the Echo cs520 a bad review and said I was going to buy one of these. Well I did, and I'm not looking back. Very happy with the quality of the saw. Heavy and worth every sore muscle. Cost about $1100.00 out the door. A saw that can actually pull a 20" or larger bar as fast as you need it to. A pure joy to use for a woodsman. Wives, buy your husband one of these and he will marry you all over again question?? how can you compare a 50cc to a 91 cc saw? Darwin rules should apply regardless of the level of mental incompetence..

Strengths:
Very Good saw, the above posters nailed it.

Weaknesses:
Like every saw it has some issues

Summary:
BEST OF THE BEST

Strengths:
POWERFUL !!!

Weaknesses:
NONE

Summary:
the best STIHL you can buy .

Strengths:
i just baught my 660 from wilson hardwere and it started in two pulls. i spent some time ripping out the innerds of the exaust and porting the exaust hole. i run a 20'' bar through 41'' bars on my 660 . the simple mods made the 660 run faster than a stock 880. the best stihl hands down

Weaknesses:
no drink despenser and it didnt come with a E3 sparkplug

Summary:
Excellent saw, only slightly let down by it's crappy chain brake!

Strengths:
Great powerful saw, munches through anything I put it to. Starts first time every time excellent power to weight ratio, more so I would say than an 880, which although is more powerful, is let down by it's lardy arse weight! The 660 has the right weight and balance to be used all day even with a 36" bar, I've even used it for felling massive willow stems from a rope and harness!

Weaknesses:
Chain brake is a bit crap, it's difficult to release and stiff to engage, the hand guard also fouls on the top of the exhaust, I've had it apart and can't find anything out of place or broken.

Summary:
I've heard great things about the MS 660, and my MS 250 has been awesome so far, so I had great expectations. But after a short while, and three cylinders, I'm quite unhappy with this unit. I've done all I can find in the manual, not sure what to do to prevent premature destruction of what I thought was a powerful saw.

Strengths:
Great power, for awhile. I bought an Alaskan Chain Saw mill and tried it with my Stihl MS 250. It worked, but was way too slow on a 13" diameter red oak. Then I took a chance on a used MS 660 on e-bay, bought a new 36" bar and new ripping chain. That was impressive indeed! 5-10 times faster!

Weaknesses:
After about 50 square feet of cutting, chainsaw died, never to start again. Dealer confirmed a scored cylinder, so I bought a new one. After about 50 square feet of cutting with a brand new MS 660, same problem. (Dealer showed me the scored cylinder.) Stihl replaced top end under warranty and I went at another log. After 30 square feet of milling (yes, only 30 square feet) this new top end has lost compression (150 psi just dropped to 140 psi). Both scored cylinders dropped to 90 psi before failing.

Summary:
great saw would recommend it to anyone who is serious about cutting wood of any size.

Strengths:
Powerful enough to cut most anything, light enough to use all day with a 25 inch bar, will handle a big bar, and outperform all others in its class! balances perfectly with a 25 inch bar, and is none too shabby with a 36 inch solid bar either.

Weaknesses:
air filter clogs rapidly, thus needs to be cleaned every tank of fuel religiously.

Summary:
best saw ive ever had

Strengths:
eats huskys

Weaknesses:
none

Summary:
not sure if I would buy another 660 .... maybe time for Husk...

Strengths:
Not good for milling "Alaskan"

Weaknesses:
Scored 2 heads so far with min. 20 ft

Summary:
I bought saw 3 or 4 years ago and never been disapointed with it, mostly just impressed. This saw has cut alot of wood, "big trees" and as long as you have plenty of gas mixed up with you it will do it all day long. I have only owned Stihl saws, have 3, ms 660 034 super and 025 and none have let me down and left me hanging, especialy the 025 it rides on the dozer with me all the time.

Strengths:
it has got the kind of power that you want to have a good hold of. It just wont give up. You put it in the wood, try to make it stall and it just wont. I do like that. All with a 36" bar and chipper chain. It dose have the displacment of a small dirt bike though.

Weaknesses:
It dose like its gas. that will come with the horse power though.

Summary:
Only ran 1 tank so far.

Strengths:
Big saw powerful saw. Christmas present from my wife. I have huge white oak trees that are dying. The biggest is 6'+.. Also cut firewood for home use.

Weaknesses:
Non so far.

Summary:
For the guy that keeps scoring cylinders that should tell you that you are not mixing your fuel/oil correctly (2.6 oz.per gal)or the oil you are using is junk.

Strengths:
The perfect saw

Weaknesses:
Absolutely NONE

Summary:
Best saw on the market!

Strengths:
Had this saw for 2 years and use it all the time. POWERFUL!!!!!! Will own another.......

Weaknesses:
Take lots of fuel. Small price to pay for the preformance it gives