Hello,
I have a TAD 150 Signature tube preamp. Please check Audiogon discussion and google.com. It's a darn good preamp for the money. The Signature version if the factory modded version. The TAD has 2 sets of outputs, ALPs remote volume control, phono section, headphone jack. Uses (2) 12AX7 or 12AU7 or 12AT7 tubes so tube rolling is not expesnive unless you go with exotic tubes. Tube life is long - 1000's of hours unlike my former Audible Illusions preamp which just chewed tubes. I'd be looking for more than $600 but not all that much more. Again check around. I don't think you'll do better for the money.
Thanks,
Paul