Preamp match to Theta Enterprise amps?

How would one determine what is the best preamp to match up with a solid state Theta Enterprise amp(s)? Should it also be a solid-state pre or can it be a tube-pre? Appreciate your help!
I am using a Gill Audio Alana that David Gill/Joe Fratus went through and upgraded for me. But even before they did their work on it, it blew me away in that it sounded so non-electronic/real. I had demo'd quite a few pre-amps and this one was the first to really set me back in amazement. It's a tube pre-amp BTW with three tubes total.
how do you like your enterprise? I just bought a pair and it on the way next week. I can't wait!!!!