[RallyBob]

Yup, they work pretty well as far as limited slips go. However, keep in mind that the unit does not replace/eliminate the stock Opel side gears and spider gears in the differential, unlike a Quaife or ZF limited slip. That being said, the differential is still very breakable, I've broken three Opel rear axles with the friction-block type differential (most recently this past fall), simply because having both tires grip now puts more loading on the stock spider gears, and they've shattered. With sticky tires, watch out, they're not indestructable.

Bob

 

[RallyBob]

You will have to install a ZF or Quaife limited slip, the Phantom grip will not make it stronger, it will only act as a limited slip.

Bob