My own E55 has had, OEM, K&N, piper cross, and currently IGT, however, if your just a road user with your car, OEM or K&N would do you proud.
On track though, my own car has always sounded and felt better with the Piper cross filters, but as one poster here, the things just collapse, they seem to get sucked into the intake, tearing the surround moulding, changed mine, at least 3-4 times, with very low mileage, really annoying, but currently running with IGT filters, had them on at our Spa trip, but never really got a chance to open the car up fully, as I was a total novice there, but, am at Goodwood on Saturday, with a couple of guys here, a track I know well, and will be interesting to see how these IGT perform, if not good, I will have no hesitation to reverting back to Pipercross, and just swap the filters out on a regular basis, its a potential ongoing nusiance, but at least the car will run fine when needed

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