Help Me Choose a Preamp

Looking for a two channel preamp to mate up with my Muse 175 monoblocks (driving Martin Logan SL3s, about to be replaced with PSB Synchrony 1s), which I believe has an input impedance of 51K. Lack of a phono stage is not a deal breaker, and remote volume & a home theater processor bypass would be nice, but neither is a must. Knowing that I can't have it all, I value a transparent 3D midrange and big soundstage over great top and bottom extension.

My budget is around $700. so I'm thinking an Adcom GFP-750 or ARC LS3 might be ideal. I do like the idea of tubes, but I've been away from the hobby for twenty years, so I don't really know what is good in that range.

Thanks for any guidance.

Bobby