We had them at our shop for a while... and while they're good, clean units, they're just not all that exciting.
There is nothing about the 2.2 preamp that I didn't think a John Hardy didn't do with a good measure more excitment, as well as a good measure of greater depth and dimension... for a few hundred bucks less... which is why M-A took a pass on the Buzz pre-amps. There's nothing wrong with the Buzz that we found, it just wasn't special enough in our opinion to stick out from the crowd... they make a smaller 1 RU one that I haven't tried that is a measure less expensive than the 2.2, I don't know how they achieved the price reduction, but if it sounds like the 2.2, it's probably not a bad deal for the money.
The compressor... I had a couple of issues with the compressor. This unit I definitely felt lacked the depth I look for in a compressor, especially an optical attenuator based compressor. To me, the best reason to use a compressor that is based around an optical attenuator is because of a seeming depth of audio that can be achieved, as well as the obvious dynamic range reduction aspects. A well implemented "opto" circuit should leave me with a sense of intimacy, a sense of closeness... two examples of compressors I really love that are based around optical attenuators are the Pendulum Audio OCL-2 and the Manley Labs "Dual Electro-Optical" compressor. These units impart a depth and musicality to the sound that other compressor don't. They don't quite have the control over the audio that a FET based compressor or even delta-MU based compressor might have, but they do have a sweetness to the sound that is very often a welcome event.
With the Buzz compressor I felt it lacked that depth, that dimension. It was very clean sounding, which is a wonderful thing in some regards, but to be perfectly honest, the Pendulum can be run as cleanly as the Buzz... but can also be made to get down and dirty as well as aggressive and urgent in a manner where the Buzz was just a bit to "polite" for my taste.
From what I have heard, Tim Farrant is an excellent designer who has come up with some good, serviceable products. The products turned out by Buzz seem to be professionally built, good, servicable items. They also seem to be quite affordable which is indeed a welcome thing to our industry... but on a sonic level, I just didn't find them to be my cup of tea.
Clean is fine, but I like a level of "excitement" to the clean audio in my world... and for not that many dollars more that would be spent on the Buzz stuff, I think there are units that do "clean" in a better, in my opinion, more musical manner than the Buzz equipment. Leave it at if I walked into a gig and all that was available was Buzz equipment I wouldn't turn around and walk out of the studio... you can definitely make a very nice sounding recording with the stuff... but if I were making up the equipment list for a studio, the Buzz stuff wouldn't be on it.
I know I'm a pimp, and the store where I pimp doesn't carry the stuff... but please realize that it was an active decision based on the texture of the tonal character of the units... that the Buzz stuff didn't stand out above the other stuff that was already on our roster is why the shop doesn't carry it. It's not that it's not good stuff, because it is... it's because it wasn't able to add a tone, texture, or dimension to the audio that wasn't already available to us in what we felt was a 'deeper and more musical' event. I hope this makes some sense... the bottom line is I'm certainly not "dissing" it... it just didn't knock my socks off.
Peace.