One of the ff members uses an aem filter in place of the kandn that came with his 57-2559 kit. From the look of things, it is easier to clean (just soap and water vs oil cleaning) and just as effective as the original filter. But in his case we are not talking about the entire aem kit. And as dung put it, the hydrolock issue really doesn't come up unless you are trying to fjord a river or something equally stupid.
Also, my kit came with a drylock cover for the whole filter...they're $20 a pop but they help keep the air flowing and the water out. I suggest you look no further than a kandn fipk II kit for optimal bang for your buck. Then again you don't have to think twice about most of these cai's. Have a blast!