This hasn't turned into a valve vs. transistor argument, has it? Oh, well, since it has, I s'pose I'd better get my twopennorth in.
For sound reproduction, you need to get as close to the original sound as possible. Use solid state.
If you ARE the original sound, do what sounds good. This usually means valves, and a certain amount of overdriving, giving a nice mix of harmonics.
Overdriving solid state amplifiers gives rise to a different harmonic mix, a lot of high harmonics and abrupt transitions, tending to sound more like filing a bit of steel sticking too far out of the vise.