I wouldn't get the bypass valve. Well acutally, I didnt.
The extreme chances that you will ever need it are so remote.... you won't need it.
PLUS, I've heard of people saying the bypass valves foam breaks off and renders it uselss and isn't covered by warranty.
I think, if your going to get a CAI. Get a CAI. If your thinking of getting a CAI with a bypass valve, it's better to just leave it stock. You won't see gains with a bypass valve... and they look totally :ghey: