800u advantage over 800a?

Is there and advantage to using a U model vs. an A model (for the 800 - or 900 announced recently)?

I will be using this only on an Athlon board - NF7-s which supports both....

Anything else? Is there a weight/stability issue with the A, better perfomance on U, better connection with U?

its really a matter of personally choice. People say the bolts are more secure. Personally i think Socket heatsinks are easier to put on. It takes less time and have no worries about applying the right pressure to the core. The performance for the heatsinks should be the same.
If money is tight then the A modle would be better since it'll save you a few bucks too.

performance is equal, U version can later be transfered on to a P4 if you would ever like, personally if i were building right now it would be a P4 rig

Well not really an issue- only gonna be used on an athlon and i'm not worried about future systems...

Well, if you don't think about future rigs, I'd go with the A. That's just my opinion since if you're going to be removing the motherboard a lot, it's really annoying to have to deal with the bolts, nuts etc. And if you lose one of those pieces, you have to wait for ThermalRight to get you another kit.

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