This is gonna sound really bad, but I scored a goal like Ibra's in a school match years ago. I really don't think it's as difficult as people make out.
Cahill's is probably the best finish, but I'm always a bit skeptical of how much luck is involved with those one touch finishes. It's almost a bit of a fluke.
Rodriguez's goal is amazing for so many reasons, and that's why I'd vote that as the best.