They offer only BTC or I can mine some other currency also? Bitcoin mining is very expensive while we still have coins that are good on exchanges and easy to mine. Let me know if there are other options available on btc also.
I will never suggest you to try this service but you can mine only ethereum as another option for bitcoin. This service has a very high possibility to be a scam service dude. You should be careful with all of your money.
I think its best to test the legitimacy of this service by investing a few bucks from multiple accounts. If the service proves to be legitimate then you can jump with rest of your capital.