Genesis mining is one of the old companies and is obviously legit.
Obviously legit? Well, there is only one single way to prove legitimacy, and that's providing people what they for so long have been asking for ~ the Bitcoin mining addresses their block rewards flow into.
Since GM's very first day, people have been asking for these addresses, but GM for obvious reasons never responded to any of these requests ~ it's pathetic that people believe they are legit.
There is really no reason for GM to try to hide these addresses from the public, since everything is open for anyone to look through anyway. That's Bitcoin's transparent nature ~ there is nothing that one can hide.
Actually it's really suspicious as they are not providing the address of mining blocks.
Then i think it's better to not use that website sooner or later they will scam for sure.