Common roll over requirements is between 35x-50x at least which is really something surprising and it wouldnt really matter at all because you would be needing extreme luck before you could really make some withdrawals out from it but it doesnt mean that its impossible because there are some whom do able to experience it.
Generally you would really be needing extreme luck for you to do so but why would really be minding off about this matter if you do just only came here for the sake of entertainment?
Talking some income or minding about getting profits out of bonuses arent something that you should be serious.
I do agree that it requires a lot of luck, gambling 40x times on your deposit is not something easy, it is actually quite difficult to do, it is basically a way for casinos to not give anything at all by giving something that looks like you are getting it. They are telling you there is a 100% bonus, but they are actually not giving you anything at all, probably 99% of the people end up not getting it, but they still end up doing marketing on it without spending a dime, and that is the great thing about it for casinos.
If you could say "we are giving a billion dollars!!!" to people without actually giving it, you would do that as well wouldn't you? That is the type of thing I am talking about, and that is going to be valid for all casinos, it is not just about twicedice or any other specific place, this is a type of thing every casino does.