Bitcoin Miner - Antminer U2 USB 2Ghs

They seem to do a pretty sloppy job. I brought my phone in to replace the screen because it was cracked. They speedily fixed it and I tested it and it looked great. I happily left. Only to realize that I forgot to test the front camera and it turns out, that was not connected. So I brought it back the next day thinking that they just forgot a step. This time, when I got the phone back after a longer wait than before, the front camera now worked but the back cover was loose, so then i had to give it back and they added more glue. But when I looked closely, the edges of the back cover now have small cracks. It's not extremely visible but it shows that this second time, the person was not as careful when trying to pry open the cover. And then, a few days later, I noticed that the NFC function was not working anymore. I use that to pay for taxi usually. Seems like they missed another step... Don't they have some kind of checklist to make sure they have done everything when they put things back? I have decided not to bring it back because I don't feel that I can trust them to do a good job. They actually charge more than other places I called and more than if I sent it back to the manufactory but I went there because the review ratings looked good and I thought it would be quicker than sending it to the manufacturer. Really wish they were not so sloppy.