It is quite difficult to warp brakes these days.
A run out gauge is the only real way to tell, as judder can be caused by all sorts of things, giving the same symptoms.
I fitted mtec drilled / grooved 345mm on my fronts back in September.
This past few weeks I started to get brake judder, only when braking.
I jacked the car up, spin the wheels and confirmed it was only the drivers disc was 'catching' when spinning.
I think it may be due to build of friction material on the disc.
Re trying the bedding in procedure seems to have alleviated the issue for me and the juddering has gone away.
Firm braking (not emergency stop) from 60mph several times, without coming to a complete stop.
Obviously be careful if doing this on a public road!
Do this a few times on the same journey, then let the brakes cool and do again.
Jas