pass aleph 5 is rated 60W/ch pure class A. The way it drives the speakers even with low efficiency it would seem to me that it works at least twice the rated power. I'm not realy sure if it does switch to B after it riches 60W/ch but it no worse driver than 3B-st. The musicality and mids are very close to tube performance so I guess you should only gain in performance but you might notice that your room will be much wormer since this amp is getting real hot.
Good luck!
Good luck!