I owned both a while back with the Creek replacing the Bryston. I never did warm up to the Bryston. I thought it was rather dry sounding and added a little bit of roughness (or of the "sh" sound) around voices. I enjoyed the Creek much better. It was warmer, smoother and just sounded better. For what it is worth, Stereophile agreed, giving the Creek a class "A" rating and the Bryston a class "B" You can read about both in the Stereophile archives.
One caveat to the Creek is unless you add the optional gain module, the unit is passive (unity gain.) It has an excellent Alps volume control with remote. However, without the module, you have to be careful about matching your source components. I do not believe the Creek sounds as good with the module installed.
On the issue of power, the Creek delivers a solid 85w/ch into 8 ohms and much higher into lower impedances. However, on a purely volume level, the Creek will not play any louder than your NAD. It would be a much more refined sound.
I used it with a pair of Vandersteen 2ce Signatures. They are fairly inefficient but it drove them well.
As far which way to go, pre-power or with one of these, it depends on your room size and how loud you like to play. Pre-power opens your options up. Ultimately, you will spend more money for about the same power.
Either the Bryston or the Creek will be a step up in sound quality from NAD. You have to make the call. Also, you will need that extra set of interconnects between the pre and power amp. If you are just looking for better sound quality go with one of the integrated units.
