You could debate this until the end of time. If you are willing to grind it out in order to slowly - but steadily - build your role I think limit is a much more probitable game. In no-limit, a single mistake can destroy a bankroll you just worked for the past 8 hours building up. That is why all the big money players - with a few exceptions - stick to playing limit in cash games. That is why until the big poker wave hit, you rarely saw people playing no-limt cash games. Obviously, if you are far more skilled than your opponent, no-limit is likey the better game because your hourly rate will likely be much larger. So, as is the answer with every poker question, "It all depends."