Hahaha! I replied to this thread in 2013, 11 years after it was started in 2002. Now here it is again 9 years later and my 51 is still running perfect on the factory top end, still looks mint. One of my favorite saws for sure. Just cut up two cords of oak with it a few weeks ago. Damn saw gonna outlive me.
FWIW, I have a 55 that doesn't get used nearly as much as the 51. The 55 has a .375 chain, doesn't feel as good as the 51 with the .325 chain. Going to swap to a .325 on the 55 one day and compare them again, maybe this fall. Too hot to play chain saw games.
My list to choose from, all Husky:
36
42
350
51
55
61 x2
365 special
365xt
272xp
372xp
288xp
The 350, or 51 get used the most. The 36 had proven itself to be a great little saw for 5 years until I got the 51, now I rarely use it. Bought it new in '92, first saw. 30 years later, that's my list. Not a professional, but I do a lot of storm clean up, and nuisance tree removal. So far no accidents, just long, hard satisfying days of wood cutting.