I got the SSAC variety and have been very pleased with the additional response. Like others fitment was a pain... And I was too lazy to make a bracket for the passenger side. A post on that would be GREAT!! I was even too lazy to zip tie it. Just holding on with the driver side bracket, intercooler hoses. It's not going anywhere. Seems to work great for the price....
However, if someone were inclined to pay for QUALITY....
There's really only two choices if you're going to throw down the big bucks:
APS
With the significantly lower pressure drop (less than 0.02 Bar / 0.3 psi at 240 kW / 320 hp across the intercooler and 1.6 psi total pressure drop including the throttle body)
http://www.airpowersystems.com/wrx/my01/tmic.htm
HYPERFLOW
http://www.xxtuning.com/xxstore/prod...roducts_id=142
http://hyperflow.com.au/index-2.html