zoodad mod
From what I see Dave, the zoodad hopes to allow a ram air (or cold air) effect. It does this by taking air for the filter from the front of the rad (just behind the grill), instead of the normal air intake behind the rad (which is a cleaner source, but warmer). While this sounds good, I know from past experience that you will end up vacuuming up a lot more bugs, dust, small road stones, etc that would normally not get into the filter. Go on any long road trip during the buggy season and look at your grill. I can tell you that around here, the rads themselves can get clogged from the dead insects alone. This will mean that the filter will only pack up that much faster. Heavy rain will be forced into the filter, which won't do it any good either. On the slideshow, I saw that he used sink mesh traps at the zoodad entry hole. That will clog up fast during bug season, and wet snow would ice it up fast also.
I had a Fiero in my younger days that I modded with a side ram air scoop, and a high flow washable cotton/oil filter. When it was time to clean the filter, I used to spend a long time just knocking the gravel out of it. I used to do a lot of top speed runs, and I never did see any power increase that netted any more mph.
From what I can see, the zoodad may result in a slightly cooler intake air temperature, at the cost of filter longevity, and possible clogging at critical times, especially in the freezing temperatures with precipitation.