I'm a paltry player on Stake in general I guess, though it really depends on the month and the kind of wagering I tend to do. If I got big on dice, then I try to maximise lottery tickets (and yes I know it's kind of pointless haha), then I can easily get double-digit bonus, but hardly near $50...

I haven't got any post monthly that I can see yet though, just the 10 day Christmas countdown one.