Welcome to HAN. There are millions of threads regarding this topic already, so if you could search next time, that would be great.
To answer your question, they are all pretty much the same HP wise. The best one, IMO, would be the Comptech Icebox. It prevents hydrolock and produces some HP gains. HP gains will be pretty lame with any intake you go with but that is my favorite. And it is made by Comptech, so you know it is good.