I mainly used Nitrogensports and as far as my own experienced is concerned, never deal with major problems here. May we know what experienced you have on Nitrogensports that turned out to be one of your blacklist in terms of sports betting sites?
Long history.. they fake your bets if you are about to win big, dont answer emails to reset 2FA and ban you and your IP if you try to get a response on forums of what is happening. Not going back there like never. well if you check reddit or some posts in bitcointalk i'm not the only one. They have a big list of players, but when they want they will kick one by one. I dont know how they're still on the top of reviews since a lot of ppl have problems on it, must be paying for reviews. It's that thing .. You only believe when it happens to you.