To JAB: I play classical guitar for ambient gigs using a Yamaha classical acoustic-electric.

I've been getting the best sound and volume from a Roland Cube-40. It covers rooms as large 1200 person capacity with lots of room to spare.

The best sound I have had from a battery amp is from the Crate 30W Taxi. Used it for Weddings out in golf courses and farmers fields.

In both cases, I rarely have to eq the guitar or the amps (everything "flat") and I run the guitar volume at 5-6 for a clean sound.

Hope that helps your decision,
DK