Yeah I think Bitmain has a pretty good reputation, they sell thousands and you don´t hear a lot
of bad experiences.
They say on their website, that you have to pay within 1h after you completed your order,
otherwise the system can´t confirm your payment due to the high volume.
In that case you have to contact the support.
Go to their support site, you'll hear of hundreds of bad experiences within the last month.
I'll tell you all about my bad experience. I wired them $1200 the day I placed my order, and seven weeks later, my order is still marked 'unpaid'.
Their support staff has contacted me several times, they always ask for the same BS, I give it to them, they come back two weeks later and ask for it again. Eventually one of them finds my money, shows me a screenshot of where they did receive it, and they still didn't mark my order as paid. That was 3-4 weeks ago.
They just contacted me again last night, and asked for the same info that was already attached to the support thread they were responding to.
Bitmain is
terrible and incompetent.