The performance difference between the two is somewhat negligible. Having said that, the CAI does yield lower intake temperatures which should lead to higher gains. I chose the safer route (SRI) myself since I live in Maine, also a cold and wet environment. I feel a lot more comfortable with that under my hood.
If you're going to go with the CAI, I would definitely invest in some sort of hydroshield. No reason to tempt hydro-lock fate.
-Jay
