I really like my 066, and it spends most of its time with 32 inch bar, although has spends a lot of time with a 36 inch and occasionally spends part of a day with a 42 inch. Great grunt and power to weight.
I wish it were smoother, though, and it bothers my hands a bit after a while, especially after a couple of long days in a row.
I bought it new about 5 years ago, and after I ran it awhile I thought maybe it was just mine that was a bit buzzy so I went back to the dealer and they ran it and said it was the same as any other one. They fired up a new one for me to run and a couple of used ones they were servicing. All ran great, but had the same vibration level to my hands. I ended up buying a 395 that day thinking I would sell the 066 (yea right, sell a saw...). But other than the vibration I like that saw enough I could not bear to part with it even though I run my 395 most of the time I need a medium size saw.
I was told that sometime in the past Stihl lightened the flywheel on the 066 to increase throttle response and it made them a bit buzzier. Anyone know if this is true?
Note: My hands are more sensitive than mosts because they have had a tough life, and I realize that what I consider buzzy is smooth enough to others. But for example, I find my 7900 quite acceptably smooth in the cut and my 395 great in that regard.