I know there have been several people who have mashed engines because of CAI's but as you say - risky or forgetful - there is no reason whatsoever why CAI kits should suck up water unless you hit a seriously large pudde. I mean my golf is on coilies lowered about 50-60mm and the filter must still be a good 300mm off the ground at least. Now i don't know about you but i wouldn't be driving any hatchback through a foot deep puddle regardless of CAI or not. I know you sometimes get areas in the UK where foot deep puddles may occur at the side of the road in heavy rain but i just wait until the road ahead is clear and drive down the middle - its only been raining heaviliy enough twice in the last year for me to serisouly take caution when navigating puddles.
I don't really see them as a bigger issue than those who run their cars on like -100mm where the sump could crack if you hit a bump, thus risking loosing all the oil out of the engine and mashing it that way. Your much more likely to come across a monster speedbump and do this that suck water into your filter surely?
Also - to finish off my tuppence - for the CAI to suck water up it would in theory have to be completely submerged, although i agree that any sort of standing water above the lowest level of the filter is probably bad news!
Sorry for the essay but its the same with most things, those who have had something go wrong will always say don't do it, whereas those who have never had a problem will say do it - at the end of the day mate its up to you
