Having installed it and knowing how much cold air makes a difference to fuel/air mixture, the C.A.I. looks to be the best designed (IMO). The trick is in the intake box. The CAI unit is (almost) totally sealed
and it is insulated. The Camaro's engine compartment gets very hot, so keeping the air box insulated and isolated is a good idea. I just got my (baseline) dyno done yesterday and got 406 RWHP with a DiabloSport canned tune. See my link:
http://www.camaro5.com/forums/showthread.php?t=92676 During the tune, the Predator showed fuel trim of -7% (not bad without tweaking parameters).
The pics of the other units just show a simple plastic box without a lid (please correct me if I am wrong). The units that take the air from below run the risk of submarining (unless I am wrong here too).