Check out the Soundstage! review by Srajan Ebean on the new Bel Canto SS preamp. The interesting part is that this self-proclaimed tube-o-phile has re-thought using tubes in the preamp stage due to their inherently higher noise level potentially affecting the weak and ultra-vulnerable signal at that stage. This concept seems to make sense and may be something to consider when choosing a preamp. Of course the right thing to do is find top contenders in each format and try them against each other in your system--the answer will likely become very obvious and will be more valuable than any post you'll read here. Best of luck.
Tim
Tim