I used both tubes and ss amps when I had my 3A sigs. I lived with the ARC 100, Jeff Rowland amps, and Theta. I would say that if you really want the most out of your speakers it isn't so much tube v.s. SS as it is, bi-wire v.s. vertical bi-amping.
When I went from a HT to a strictly 2 channel system I had the extra amps (5 channel Theta) channels so, I tried vertically bi-wiring the speakers. It was like buying new speakers.
When I went from a HT to a strictly 2 channel system I had the extra amps (5 channel Theta) channels so, I tried vertically bi-wiring the speakers. It was like buying new speakers.