What makes you think those are not scam? Already checked on the forum and most of the people are giving the negative reviews about it.

You can checkout more discussion about them here: https://bitcointalk.org/index.php?topic=1726695.0


However, cloud mining is always bad way to invest our money. The ROI and network difficulty calculations along with the terms of company establishment never fits in. You never know when the company will shut down due to unprofitability raised by external and internal factors.


The only few names in the market that can sustain for long time are genesis and hash flare. But they are very big and thats why we can keep trust on them but for sure not longer times. So trade with caution when it comes to cloud stuff.