I was originally solo mining against my wallet with them, I going to point the U3's at
http://solo.ckpool.org/ next, I've just been messing around with them. I have about 7TH of hashing that I point at pools.
7TH, that's a nice little setup. I'm surprised the U3 was something that interested you with that much hash already. I have to ask, what drew you to the U3?
The U3 was the first ASIC miner I bought, somehow it didn't turn me off to mining despite all its problems.