Unless you are shooting unknown 3D the only advantage to speed is the ability to shoot a heavier arrow faster for better penetration. That being said, there are speed limits in unknown 3D classes to keep it competitive and keep the challenge there. I've shot outlaw classes where I was shooting 315fps and there was a big advantage when it came to yardage judging. Faster flatter shooting arrows means when your off a few yards on your judging, you have less drop to worry about dropping out of a scoring ring. The same can be said in a hunting situation also. It still doesn't change the fact that speed doesn't kill. Shot placement does. Worry about how well you shoot the bow and give yourself room for error in your arrow set up. If you feel comfortable shooting a speed bow with a heavy arrow and you have practiced a lot with it, you will have an advantage being able to shoot a heavy arrow fast. Again, it still doesn't matter if you don't hit where you need to.
