If you assume that solid state amps neither add nor detract from the signal, merely amplify the signal, then you may conclude that all solid state amps sound the same at the same output level so long as that output level does not provoke clipping or audible harmonic distortion.
In the real world, however ... that's a boat load of assumptions.
On the subject of boatloads ... I have some solid state amps - Anthem PVA 5, Kenwood KA9100, Harman Kardon PM665, Yamaha M80s (3), Integra M504. There are subtle differences. I don't know that any of these amps would differ in an A/B test (they might). I think you have to live with the amp for a while. You love some, you like others and some, well ...
