Hi, thanks for your reply!
I didn't take the bitcoin price into consideration. I only look at the amount of mined coins every day. The price in terms of USD comes into play at the end of the game, when the contract gets cancelled. The mentioned USD were a forecast in case the price of BTC stays constant and the amount of mined BTC decreases (due of difficulty rise?) in the same speed as it did last month.
"with hashing24 should be significantly more"
I see that the contract gets cancelled before ever getting ROI. Since every day the mined BTC decrease significantly. Yesterday I mined only half of the BTC I mined a month ago. This means, that in case the decrease keeps going, within the next month the contract gets cancelled. So it last only 2 month. I am curious what happens... Definitely hashing24 is the worst contract so far.
The best seems Hashflare followed by Genesis Mining. Even I write in a few days about Genesis Mining, I can tell that some days the payment didn't show up in the balance list. I have several tickets running here....