CAI is much better for power, the SRI is just for better flow/sound, it sucks in hot air from the engine so it's no good for power, but it does get better flow..it's basically a cheaper alternative to cold air, the only problem CAI's have is getting waterlogged(due to the fact that they're in the bumper instead of the engine) but i've never had aproblem with that and they have covers and stuff for it.