... and more reasons to not use Nicehash:

Their fee to buying hash rate is between 5% and 6% but they falsely state it's only 3%
You will usually earn less mining with them than on a pool.
You have to trust anywhere you mine to, why trust someone like them with their well know bad history.
They violate the cgminer license with 'their' firmware they distribute
There's major privacy issues with your account there since it only allows a single BTC deposit address so e.g. you can find the full history of anyone's deposits there if you know just one of their deposits.

Who knows what else they do behind the scenes ...