Adam Levy has a series on his Web site where he asks the same 13 questions to different guitarists. Recently, he asked those 13 questions to guitarist Alvin Youngblood Hart. In one question, Hart gives his opinion on what makes a good guitar:
Well, it certainly isn’t the name on the headstock. The difference is what goes on between the nut and the saddle. By that I mean, if those variables are straight, a $60 guitar will sound every bit as good as, if not better than, a $6000 guitar.
Check out the rest of the questions and Hart’s answers here.