Yup, I have both the BFG 6800 GT and the Ultra in my house right now. The GT is installed in my machine (I received that one last week from CompuPlus) and my Best Buy pre-order just arrived today for the BFG Ultra. It's still in the shrink wrap.
I planned to just take the Ultra down to BB and return it but I want to make sure I won't regret doing so in favor of the GT. So far, most people recommend keeping the GT for my rig since it's a P4 3.0 and from what I am seeing in the benchmarks, there doesn't seem to be $150 worth of difference between the cards.
Thus far, I am very happy with the GT and have not experienced a single glitch. I kinda feel like I should leave well enough alone I suppose. Also, I won't overclock the cards beyond what BFG has already done. I am not brave enough to risk such expensive hardware, even if it's minimal risk.
I just want to make sure I am thinking ahead and considering everything before I do.
I definately realize that I am fortunate that two pre-orders came but it's kinda agonizing to choose between the two!
Oh, and neither store has a restocking fee within 30 days.