To answer your open and very broad question, I'd say the generic CAI. Cold air is more dense and produces more HP than a short ram intake when all else is equal.
Theres a big thread on Nasioc that boils down to short ram. CAI is colder denser air, but not cold and dense enough to compensate for the amount of air a short ram will pull, (this is with the backing plate on the hood vent removed)
IIRC, the main thread on NASIOC talks about short rams and cai's on turbo engines. The consensus seems to be that a cai does not draw as much for a turbo as a short ram does. If you go to the NA section, you will see that cai's are favored for NA engines. I have the plastic plug for the fender that closes the opening left from the OE resonator removal but need to redo my bracketing before I can use the plug. I just got the plug the other day and haven't had time to play with it more. And yes, its the rainy/muddy season hence all the splash-up. Be sure to make sure all of the fasteners on your wheel well lining are functioning so that the new filter is as protected as it can be from water flying up into the wheel well.