Pairing of the 2

Whats the general consensus on pairing a B&K Ref5 S2 pre with an Adcom 5500? Or should I look for a B&K to match up with it? Looking around a grand or under, and I don't have the most critical ear. I have Paradigm studio 40v4's I'll be driving with this combo. Musically, old rock, new rock, alternative, and some stuff that could be reproduced by dropping a chainsaw into a metal trash can. My system has come a long way since discovering this site and it's knowledgeable members. All responses appreciated, even sarcasm! (I do have a sense of humor)
Sprink, I like your attitude. I owned a B&K 570 S2 which is a bit different that your Ref 5 S2 preamp and also a bit different than the B&K straight amps. This being recognized I found the 507 S2 to be bright (yes, and I don't use that term loosely). I found that listening to a Nora Jone's CD was unlistenable to the point I had planned to write her a letter and tell her how aweful here mastering was done and that she (with her beautiful live voice) should do something about it.

I understand the B&K amps are better by themselves, but I cannot really confirm this.

I have also owned Adcom in the past, two 565 mono blocks that I thought were pretty darn good. I think (at least years ago), that Adcom delivered a lot for their price.

Because this is my history with these two company's I would err on the side of the Adcom (or something else, probably if it were up to me).

Only with certain brands do I believe that the synergy achieved between amp and preamp (Burmeister for example) is absolutely essential, and yes even sometimes a benefit over finding the better of each of the target components.

I do have a positive on B&K, they are a great company with wonderful support.
In general I prefer staying with the same manufacturer due to impedance matching issues, but this is much less of a concern with solid state. If the preamp provides balanced outputs, I would try to take advantage of that. You might also consider an ATI AT2002 balanced amp.