Similar issue, I found the Saitechi one I bought to be very flaky. Depending on the particular bootup of BFG miner, I can get anywhere from 9-300Mh/s (averages about 120) on a single stick ( got it to run 3 at full speed, but the port arrangement and sticks used are probably random), and my errors get near 75% after about 15 minutes on all five. I know it's not the erupters, they run fine in my computer.