....this harmonic balancing is also why it is CRITICAL to use a dual mass flywheel like the OEM unit instead of an aftermarket single mass flywheel.
There are all kinds of weird harmonics that affect a vehicle when all these parts are spinning around as you go down the road.
By the way, I DO think the Fabspeed sounds AWESOME.
I just couldn't live with it on a real world, cross-country driving 986.
For a weekend toy? Sure! I'd slap one on.
But my car is used for cross-country vacation trips in addition to just cruising down to the local car show.