I looked for ages to upgrade my Jspecs.
Ended up with UK Callipers, Goodridge Lines, Motul 600, CW Fast Road Pads and DBA 4000 Wiper Slot Front & Rear Discs.
DBA seemed to have the best comments for a sensible budget, although there didn’t seem to be as much info on the other makes.
EDIT: 'I belive some tested/used some and found DBA to warp the least'
As stated before, stay away from drilled discs, only from what everyone has said.
See the attachment about plain, slotted & drilled discs.
Part reasoning as well was DBA seemed to offer all the tech stuff and performance, where as the others didn’t – or wasn’t readily available.
Also the slotted DBA’s don’t make any noise what so ever, which I know some slotted ones do.
Their ‘PAW’ print design in the cavity (rather than the conventional web/fin) is supposed to offer 20% better ventilation as well.
They also have 3 colour markings on them as well that change colour when they go above given temperatures, so you can see if you’ve been caning the hell out of them.
They seemed to have put a bit of thought it to it and didn’t hide away from issuing info. Application_Chart.pdf Major_Considerations_Track.pdf