Ages ago I relied heavily on specifications; that was when I was into SS. Once I discovered how much better tubes sounded, even when SS had better specs, I quit relying so heavily on specs.
Impedance is a very important spec for apparent reasons. Presently, I have plans on the drawing board that I don't think will include auditions. In the past, auditioning would have been the first step. Now that high end salons are no longer an option, I'll be relying heavily on past knowledge of "sonic signatures"; such as the difference between CJ and ARC, instead of auditioning; also the "Stereophile" reviews will mean a lot; preferably only "A" ranked equipment. All of that of course will depend on an "A" ranked bankroll, which is pending.
Since auditioning is absolutely out of the question, I will rely heavily on past knowledge, plus reviews, and only the most important specs. I've noticed that within a certain price range, specs are very close.
Fortunately, if the pending bankroll does not materialize, I'll remain comfortably in place. As a footnote, I noticed everything I own costs over twice as much now.