I've had two Adcoms, the 535 and the 5500. I've also had two McCormack's, the DNA 0.5 and 1.0 monoblocks. The McCormacks are head and shoulders above the Adcoms in every way. I had severe listener fatigue problems with the Adcoms, which improved when I bought the fist McCormacks.
There is no doubt that will get you closer to where you want to be. Also, don't underestimate the 0.5's ability to drive demanding speakers. It did much bettery with my maggies (1.6QR's) than the 200 WPC Adcom did. Also, most of the unmodified amps have 100 kOhm input impedance, so any pre will drive them. I'd say go for it then see where you are.
There is no doubt that will get you closer to where you want to be. Also, don't underestimate the 0.5's ability to drive demanding speakers. It did much bettery with my maggies (1.6QR's) than the 200 WPC Adcom did. Also, most of the unmodified amps have 100 kOhm input impedance, so any pre will drive them. I'd say go for it then see where you are.