In a nutshell:
The advantages you will see from expensive Induction kits are nearly non existent, in some cases like a Viper the kits can be very detrimental! The most cost effective option is the ITG panel filter dropped in the standard box - done. One of the best aspects of this is that it is life long - you will never need to buy another panel filter again aside from cleaning it once in a while.
The next part of the equation is to remove the acoustic valve, a limiting valve that was designed to reduce engine noise to comply with Swiss regs IIRC.
You can remove the valve & leave the cold air feed (although it is very poor and often very narrow near the airbox where it is bent past the battery) so you can also replace this with a neoprene feed down to the same location as the acoustic valve was once positioned. Some people mount this in the fog light hole/front grill for a direct feed, but of course you can then run into all sorts of problems with water ingress etc, so not really worth the risk for such a minimal (if any) increase in power.
The last reason why people buy kits such as the Simota Aeroform is to gain that induction roar, this noise can be obtained in a similar fashion in the 1*2s by just removing the right hand CAF (looking in the bay from the front of the car) from the standard box completely, the difference between having the feed & not is minimal, and the airbox will generate a much throatier note as a result.
Removing the feed also takes the acoustic valve out of the equation so there is no need to remove it (unless your a weight saving freak lol)
Hope that helps.