I thought I'd give these guys a try some time ago, I ordered a 500 mh/s pack but sent a few extra coins by accident (sloppy number keying). This ~0.03 extra btc showed in my investment account for a while, but one day disappeared.
So I filled out a contact form describing the problem, and got this response back (response received Jun 16):
Let us check this issue, your remaining ~0.03 should be there, so when we found the problem, we let you know and you should see your funds there.
hashrack.com
Hashrack Team
No biggie, so I waited 3 weeks, but still nothing. At this point, I'm rather irritated, so I go to fill out another contact form, and lo and behold, the page now gives an error. So I replied to the original email i received from hashrack, simply requesting a refund. This was over a week ago and to be honest I'd be surprised if I ever get a response.
tl;dr: Money went missing, communication went dry, don't trust this company.
