The main complaint about the K&N filters is basically that while they let more air into the motor, at the same time they let in too much dirt and airborne particulate matter into the motor.

This has been debated before on the forum, and I personally elected to stay with the factory Mercedes Benz air filter.

I doubt you will be able to find one for under $42.00 though

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1991 560 SEC AMG, 199k <---- 300 hp 10:1 ECE euro HV ...

1995 E 420, 170k "The Red Plum" (sold)

2015 BMW 535i xdrive awd Stage 1 DINAN, 6k, <----364 hp

1967 Mercury Cougar, 49k

2013 Jaguar XF, 20k <----340 hp Supercharged, All Wheel Drive (sold)