I have an 88, and a 66. I've used a 64 YEARS ago, and it's not a bad saw, but I don't think they have made it in over 10 years now, so as the pig already stated, parts might start getting hard to come by. Also, putting a 20" bar on a 64, or 66 is overkill. I've got 362's with 20" bars and they rip, I've put a 25" bar on my 66 before and that REALLY rips... so to put a 20" is just foolish, and burning far more fuel than you need, not to mention the weight. Now the 88, that saw unless you are into bigger wood often, or have other plans for it is just a big hunk of metal and plastic to have laying around. I've got a 59" bar and a 41" bar for mine, and hate using it. The saw is big, heavy, and cuts slower than the 66. If you are up for spending $1250, I'd say just go buy a brand new 660 with a full factory warranty, and be done with it.