I asked the same question several time, but no one was really able to share experiences.

Asking the operator is a good idea in general, but I doubt he would state "Yeah, the plan is to run away with your coins when I collected enough of them.
So it would be great to have some reports from users with funds on the site for more than a few days. After all that scams, it' better to be more careful when giving away control over your coins.