It's a great question - one that I've been laboring over. In my area, there aren't many tractor dealers, and the ones that are here don't do any kind of volume at all. I visited them, and the typical experience was that I would walk in, stand around for a while listening to the crickets chirp, and then go out on their lot to look for myself. Selection was EXTREMELY limited (my NH dealer had one TC40 on the lot, and that was it..., I mean that was IT - nothing else). When I finally got to communicate with a sales person over the phone, he told me that "we've got the best selection anywhere in this part of the state, blah, blah, blah...". He was a nice guy, I liked him, and would buy from him if they had prices that were anywhere near competitive.
So, I haven't decided what I'm going to buy yet, but I've definitely decided that I'm going to buy from one of the folks I've talked to out of state. Even over the phone I feel like they pay more attention to me than the locals. Warranty work might be a problem, but I'll just have to deal with that when and if the time comes.
One interesting thing that I did find out the other day - I talked to Buck at EFC Construction in WA about one of the new TYM tractors, and the warranty policy on those units is pretty good. In short, they will let you get the tractor serviced at any tractor shop, and TYM will pay full shop rates for the work. Most manufacturers only pay a cut-rate on warranty work, and I could see plenty of reputable shops being really happy to work on an outside unit if it paid like that.