The PC3200 is CH5, the 3700 is BH5. There isn't a huge price difference. I tried both, and for my rig the BH5 was worth the extra money.
Both are good, and for most users either would be fine. In dual channel Intel applications (especially on Abits) the BH5s have a lot more potential. For other applications the CH5 is very good, usually equaling BH5s clock speed but with slightly looser timings.