I have the 501s and they work very well with Wilson Alexandrias, which need alot of current to sound best. In my experience, these amps need a long break-in period (e.g., at least 600 hours), dedicated lines, high quality power cords and a power conditioner that doesn't limit current. I've had excellent results with Elrod Statement cords and the Isoclean Model 80 A3 conditioner, which can pass 80 amps of current.
