I was one of the duped, so I can confirm cloudmining.website is a Ponzi.  I currently have 2.57 TH under contract and yesterday received 0.00056276 BTC, far below what I should.  When I first joined the site, payouts were in line with the amount of hashing power I had purchased.  Then, true to the form of a Ponzi, they dwindled to almost nothing.  The administrator has ignored my inquiries and is keeping my BTC.