many people here know that all doublers will Scam, because 100% profit in 4 days does not exist
(someone wins, someone loses)
(P.S. I am newbie)
youre quite wrong there
Do they trade/earn your profit? No
Are they ponzis? Yes
Has there been any sites that actually pay double?
Yes!! BitcoinsX2, Flexybit, and many more
If you get in first and DO NOT invest in "hourly paying" sites then you can profit, I'm up 2.4BTC in the last few months