Has anyone fitted one of these and if so are they better than a box performance filter?

Yes
Yes

Beware of 'apparent' MAF sensor failures - no hard evidence, just be warned!

Yes and yes

Ive got to say when i first got my Scoob, first on the list was a 57i Kit. Used it for a while....

Makes lots of noise
Increase fuel consumption
Better throttle response

Having said all this i have just conducted an experiment, i had removed the resonator and put a cold air feed in the front wing, I then put the standard airbox back on and added a JR high flow panel filter

Result is the car is alot quieter
Still feels the same has the same amount of pull and throttle responce
Slightly better on fuel...

So if you want that induction growl and better responce go for it.

If you want the same but without the noise put a high flow panel filter in with a cold air feed, obveously there is a sligt increase in noise with the resonator removed but nothing like the growl the 57i kit makes...

just my opinion..

sorry to hijack this thread.. but..

i have a my96 wrx with a k&n panel filter (which has done lots of miles now and probably needs replacing anyway).. you guys are saying i will *notice* gains if i change it for the k&n induction kit?

any preferred suppliers that can offer it good value for money?

apart from the noise, cant imagine you will see much diffeence..

unless you ut a cold air feed in..

any link to a reference on how to do this?

thanks!

have a look at my projects page on my website..

look in profile for a link