This topic came up at a meet last weekend. One of the attendee's said "I've got a set of the Kintix discs fitted to my Zed". I instantly ran to the front of his car to look at the egg shaped, cracked, split and dangerous discs. Guess what, they were fine.
They're fitted to a daily driver Zed and have covered just over 6000 miles. There were no lips on the discs and they looked in great condition. The owner reported no issues with them at all and they performed as brakes should. Unfortunately I forgot to ask what pads he was using with them.
I think a key factor to a brake set up's performance is the bed-in procedure. As long as this is followed, I don't think your average Joe, using his/her Zed on the road will have any issues.
Just thought I'd add a bit of 'real world' feedback to accompany flyboy's and also to say, I've just ordered me a pair of fronts with some Brembo pads.
I'll report back after a few 1000 miles