I just recently moved up to $50 NL. I wasn't really comfortable with it at first either but I think the only way to get comfortable is to play it. I doubt it will really matter if you move up now or when you hit 1500. You can always move down as someone already said. Your win rate is similar to mine at both $10 NL and $25 NL and I think you should be able to beat $50 NL too. I only have 5000 hands at $50 NL but I've been running at 2 ptBB/100 and I was breaking even the first 3000 hands. I'm not completely comfortable with it yet, but I think I just need to prove to myself that I can beat the game consistently.