I am running an ARC SP6 (with mods towards an 8, because I bought it not knowing it was so butchered) with my Counterpoint SA12 (hybrid, like yours), powering Acoustats, and seems to work out well. The one caveat- this combination is slightly anemic on bass, the result of the Acoustats being a hard to drive load.(*)
*(I wouldn't claim this as too much of a fault considering the music preferences you list- I listen to syncopated musics with a tendency to be heavy on rhythm, eg; Cuban, African, and world, and "classical" music and it is easily within acceptable limits- I seldom find it lacking, but thought I would mention it.)
So, if you're listening to any reasonably efficient speakers, the combination seems to work out well- I would recommend an ARC SP8 as they are not too astronomical in price and findable.
I have the luxury of listening to many different types of gear, from the average to the esoteric as I work at a Hi-Fi repair shop one day per week for years now, the exposure being my "pay"... the point is that it seems that these hybrid amps coupled with tube pre-amps do very well.
Good luck!
