This is one of those subjects where everyone has an opinion. Here's mine.
I once worked for Caesar's and helped run a computer service that feed sports and para-mutual odds to smaller casinos and bookies. Most of my friends were dealers or pit bosses or otherwise "in the business." What did I learn? It's called gambling (ok, gaming by the casinos) for a reason. Odds are odds. There is no such thing as a streak you can anticipate in roulette - if it's an honest wheel. Just like flipping a coin heads 100 times in a row is still only 50/50 on getting tails on the next flip. That's the probability for you.
Cards - or more precisely Black Jack ... OK, that's not as random as a wheel. If you count (or remember) what has already been played, sometimes you can improve your odds. That is assuming there is an imbalance in the remaining cards. That is why casinos are watching and quick to ban you if they catch on. There is no appeal process. They make the rules and they get to decide.
I watched more than a few "professional gamblers" come and go. For various reasons. Horses were the worst for people making a buck selling information, usually made up BS. If someone did actually have inside info it was illegal or worse - at least for the horses.
Anyway, pay someone for a "system" and you are already gambling. And the odds are against you. Maybe I'm wrong, but that's my opinion and I'm sticking with it. So, don't bother trying to convince me otherwise.
