I can't give you personal experiences about Redbet at all, however I can tell you what I know about them off the top of my head though.
Redbet (Not Rated) is a skin of
24HPoker and is a publicly traded company in Stockholm (Rbet). Also, they are regulated by the British authorities. The liquidity on their exchange was pretty bad IMO and the 4% isn't really attractive to me at all. As far as payout issues go, I don't recall reading anything bad about them in that regard at all. So I would have to assume they are fairly safe.