As far as I remember, if you're sticking with the Windows games...none.
But, in my opinion, if you can't 1CC Normal, you're certainly not ready for Extra anyway.
Download the vsync patch and see if that fixes IN. Also try MoF; its Normal is also pretty easy.
But then again, I wouldn't feel ashamed going to Easy. That's how I started, and when I was good enough at that, I moved to Normal.