I've read a lot of reviews before I bought AHB2. Here is summary from "Absolute Sound"
Because accuracy allied to absolutely reliable performance is the goal of all the Benchmarks, they are not products that tend to attract cults or other sorts of starry-eyed enthusiasts, wholly lacking any of the quirks, foibles, idiosyncrasies, sonic flavorings, euphonic distortions, and so on that characterize the objects of most audio cults. Professionals buy Benchmark because they know the products work and are reliable and accurate—indeed, reference caliber. Music lovers buy them because they are neutral and accurate and thus reproduce the tonal character of voices and instruments correctly (and also, I presume, because they are reasonably priced, most musicians, like most other people, being typically not wealthy). But audiophiles? Well, the longer I’m in this racket, the less I sometimes think I understand what audiophiles really want except that a lot of dallying about with components, equipment swapping, and coloration matching seems to be what amuses them. I’m not sure I can in good conscience recommend this amplifier to them as I am not sure they are in search of what it offers: a precision instrument designed to perform the precisely defined task of reproducing music and sound accurately, which it does essentially to perfection. But to anyone else, the AHB2 gets as high, enthusiastic, and confident a thumbs up as my arm is capable of reaching.