I have 2 M400t's also and both work well but I will send them to Rita, one at a time just to keep her going. Of course even though they work they will benefit from a going over.
I used these bridged to drive my ALS Silvers & they did great. As good as my Sunfire really.
They are the most under rated Carver amps although Bob said they were his favorite (If you pinned him down) because they put Carver Corp. on the map.
Just my .02
Frank