If you are thinking of tube amplification, i agree CJ....Quicksilver is great too and huge bang for the buck. I would also recommend going Rowland amp if you were to make an upgrade and stay SS. My preamps up until recently proved to be the bottleneck of my system, My c-j pre sounds fantastic and I'm fairly certain it would be big $$$ to improve it. I upgraded my amps since and they too were an improvement but I honestly think that pre is so good I could upgrade my other components further and the preamp would not be outclassed.
My point, if you have a great pre there are probably better ways to spend your money.
My point, if you have a great pre there are probably better ways to spend your money.