I've got to go ahead and say that if Hugh Dean (Aspen Amplifiers) makes it, and I need it (or want it), I'll buy it. Hugh is one hell of a guy, with some really amazing products. Especially when dealing with DIY there is no one with more support. I have exchanged over 220 emails (and time on the phone) and he is still willing to help me out! I know a lot of Audio companies are good about support, but this is far beyond 'good', very far beyond. Ironically when picking out the amps & pre-amp all I cared about was sound quality, and I wound up with Aspen Amps, so it really is the best of both worlds: high quality and service! No compromises needed. So it terms of brand loyalty I'm with him. Now in the event that Aspen doesn't make it, I am very open to other companies. I will say though that I prefer dealing with smaller companies as I feel that they care more about how the customer winds up than some of the bigger companies. The small companies insure you enjoy their product while the bigger ones make sure paid then kick you out the door. I know its not true all the time, but thats just how I feel with my experiences.
Also I should say that in terms of getting parts (I know this is more like 'store loyalty' than brand) but I'm with Michael Percy and Sonic Craft all the way. I find that with both of them I get exceptional service and they are always willing to help out with a problem.
-West