As far as I can tell, yes it is. I'm sure there are some amps that sound better, but from the meets I've been at I haven't heard any that have immediately jumped out at me as significantly better (at least not enough to warrant an upgrade).
I find describing the sound quite difficult except in comparison, so these impressions are compared to the O2 (which I got to hear not so long ago at a mini-meet). I find the A2 to be a fairly detailed amp with a little bit of extra mid-range emphasis (or maybe the O2 has slightly exaggerated treble). I typically don't listen past 9-10 on the dial, and use high gain, so YMMV depending on your listening level. I find it nicely detailed without having any harsh treble, and I think it complements most of my cans, HD600 especially, quite well.
Thanks, the A2 sounds like a pretty versatile amp. I liked the first version with its warm, analog sound but i think the A2 is more neutral sounding. Wonder if it will work well with the LCD XC..