I did research on crypterra and I really believe they are legit, just look at their mining wallet balance:
https://blockchain.info/address/1N52wHoVR79PMDishab2XmRHsbekCdGquK
I got their Xmas sale of 340 MH/s of ETH for $1912, which is a deal that cannot be beat these days. I am getting paid everyday.
Check it out yourself
https://crypterra.net