I've been doing a bunch of research on this subject myself lately in an attempt to find a quality unit at a decent price. The C&R is pretty much top of the line it seems and is close to triple what the Griffin setup costs. From some research online it seems that the Griffin units are occasionally prone to leaking. I made this post on ls1tech and got a little feedback on them.....
http://ls1tech.com/forums/conversion...radiators.html
Seems the next most cost effective options are Entropy, followed by Afco. AutoRad even without the core support, RonDavis, & C&R are all big money and way overkill for my level of build. Post up what you end up deciding on as I'm on the fence on which direction to head on this.