Awesome product. I have a set of the GT discs. Stopping power is unbelievably good considering they the same size as the standard discs. You end up driving faster though coz you can stop in such a short distance.
If you do go for it, dont get the mintex pads that they supply, its crap and they squeek lil a dying pig. Spend an extra R200 and go for Ferodo Platinums... Best combination. I have it for about 20 000km now, no complaints.