Hi Charles, the amps should be broken in, their preowned, or as we say in Brooklyn, used.
Funny you should mention the best sounding maggie system you ever heard.
The best maggie system I ever heard, I owned. MG 2b's biamped with a CJ PV2ar pre, a CJ MV45a driving the hi-end and a Sumo 9 plus driving the lo-end. I also used a passive Magnepan crossover, that was many systems ago, it sounded like liquid out of the speakers.
This is my forth and final trip down the maggie isle over a 25 year span. They do need power to sound their best.