Just want to weigh-in on this thread a bit.
I picked up the newer version of the A1 recently, and I'm really liking it on my Quad ESLs (I use the originals). Value-wise this is a superb buy. Comes with a USB input and an MM phono stage. Original circuit was designed by Tim deParavicini (I'm a big fan of his work) back in the day.
This new version of the A1 is a bit more powerful than the older version (36w vs 20w), but it is all the power that I need so it works well in my system.
I'm still trying to get my head around the quality of the MM phono stage. So far I see it as just 'adequate', but I have to do some more critical listening before I really make a declaration. I'll admit to wanting to try a step-up transformer with it so that I can really put it through its paces, but I dont have a SUT, so that experiment may have to wait a while.
My weakness is for solid-state integrated amps. I've gone through about 12-15 of them in the last 10 years. One of them was the Musical Fidelity M3 Nu Vista. I loved it a lot, but was disappointed with the quality of the volume pot. The volume control on this new A1 seems to be a bit different (still not sure of the quality though...time will tell).
Anyway, just wanted to share some of my thoughts on this particular classic (or at least the new version of the old classic). If your speakers can hang with the little amount of power that this amp kicks out, I think it is a very good buy.