Re: Which neck joint do you prefer?
As far as sustain goes, I think you'd be better off with neck through or deep set neck tenon guitars. I use both bolt-ons and set necks, and I like them both. The most important thing is to make sure the neck fits nicely in the pocket. Both my Peavey and my Hamer are designed very well in that regard, and they both sustain quite well. Hamer's set neck design uses a dovetail joint that is 40% bigger than the one Gibson uses, and Hamer fits the neck joint by hand. Rather than allowing a large margin of error like Gibson does, Hamer builds the neck heel so that it's slightly larger than the pocket. A builder then sands it down by hand a little bit at a time, until it's a perfect fit. Because they build entirely by hand, I think Hamer's design is far superior to that of a typical set neck guitar.
Ryan