anybody try these instead of the stock filters? I heard that performance can increase and less black exhaust left on the swim platform?

I have a set . switched motors in 04'from 496ho's.
They did seem to help .I saw my best top end with them on.
The only problem I had was I squeezed one on the cover.
PM if you want to buy they are sitting in original boxes.

ive seen nothing. no gain nd still black transom

No gains to be had other than filtration. Mine collects a lot of hair, lint, etc. It also has no affect on the annoying IAC whistle.

Thanks, but I'm not aware of the IAC Whistle? what whistle?

I hear mostly the motor and exhaust flaps?