I feel like i can trust the XFX card because i have not heard much about diamond...however, that price on the diamond card makes me really consider it. A lot of the time things are cheaper for a reason though.... so what can anyone tell me about these card? (seems like the xfx card will in theory stay cooler because of dual fans also...right?)
Well the diamond card price is the price after price cuts. You should be able to wait for the XFX card to drop it's price like the diamond one.
To be honest, I think you're fine with the diamond one, because it's a reference model so the fan or the PCB will not be bad (yes yes, I know that reference coolers are not as good as the aftermarket coolers, but it is standard, in fact some aftermarket coolers from some brands are worse than reference coolers), yet it has good reviews. The thing that I'm worried is their customer support, haven't heard them.