I like Bitmain, they make very reliable units. Never really had to deal with their CS
I've bought S2 miner from them and after a couple months it stopped to work. I didn't overclocked the miner.
I asked their customer support about what to do. There was no response..
So, I'm agree with the TC: their CS is horrible.
And I'm not agree with Stargazer - their miners aren't reliable
