morgoth, haven't heard th SF stuff so I can't give you an answer. There seems to be some good suggestions here, and I stand behind my Rogue recommendation and I've read good things about Manley products. It seems that if a company has an element of fun to it, it will probably sound good with rock (go figure!). I'm also intrigued by the Juicy Music Peach. The looks are questionable (WTF ugly??) IMO, but the comments seem to cite characteristics that make me think it would be a good pre for the job.
As I've recently learned, impedance matching pre to amp is also important. Make sure if you get a tubed pre mated with your SS amp that the ratio of output to input is around 10-1 to start.