What could I expect to hear from a Class A amp?

Shadorne: Correct as to the unamplified nature of crossover distortion. It is only the ouput, or final, stage at which the bias point is placed near cutoff and saturation, respectively rather than centered - in a class B amp. How hard that stage is driven makes no difference as far as the amplitude of the crossover distortion since there is no amplification following that stage. But since the excursions will be greater away from the crossover point, when driven harder, any change at the crossover point (which will be insignificant anyway in an AB design) will be a smaller percentage of the overall signal. Hence, at low values of output signal any such distortion would be a larger percentage of the output signal. As to your comment regarding active speakers - absolutely true - it always makes sense to design the electronics for the load and the more known about that load allows for an easier design with less compromises.

It would be nice to know of non-Pass Class A amplifiers that perform well, and why so. Bearotti asks about Krell. At this point I am curious in just about anything Class A. The whole discussion thus far is very helpful to me as a Pass XA60.5 owner, but thus far continues to confirm what's heard through the months, in that nobody remotely comes close to Pass Lab on Class A amplifiers. Otherwise there would have been well-informed and fairly objective challenges left and right.

It would be nice to know of non-Pass Class A amplifiers that perform well, and why so.

ATC make amplifiers with what is probably a sliding bias - you get 2/3 power Class A before it reaches Class AB operating point for the final 1/3 power. I have not compared them to Pass but ATC are relatively unknown as an amplifier manufacturer whilst Pass is legendary. You are safe sticking with Pass, IMHO.

Coda makes some very good Class A amps in pure Class A and biased Class A. Recently heard the Coda S5.5 a real stunner. Also if you can find the Coda 12.0 it is a heavy contender in Class A amps.

Most of the Coda staff is former Threshold staffers, that formed their own company. So the Pass legacy is clearly evident in their product line.

"...nobody remotely comes close to Pass Lab on Class A amplifiers. Otherwise there would have been well-informed and fairly objective challenges left and right."

I'll submit Clayton Audio as a strong competitor to Pass Labs performance-wise, but they're obviously a much smaller company that sells far fewer amps so they're not close in that regard.