You measure runout with a fixed dial gauge. Floating rotors do not make a difference to this unless the carrier is warped or the mounting buttons are clagged up. The dial gauge is set up to measure what the pads feel. Not rocket science.
I came to my MTS from a KTM (excellent brakes with no problems) and 3 triumph Tigers in a row before that. I had MAJOR problems with all three bikes with brake rotors made of cheese (Thailand made Sun brand all of them) that wore out in 12K KM and warped front disks. The theory at the time was the warping was hard use heating up the rotors and then sudden cooling causing differential contraction and warping. To translate - using your brakes a bit in the rain.
I ended up replacing the whole brakes on my last 955 tiger with French made Beringer rotors and 4 spot calipers. Excellent and no problems in 50K KM.
One of the reasons I went with the MTS1200 was that I was sick of replacing inferior components like brakes and dampers. I thought I was buying a bike with the good gear fitted already.
I expect more from Brembo. Delusional?
Hmmmm.....
...and unfortunately Tim, like everything these days, whether Brembo or whatever component that's going to market on a bike at a price; something's got to give. That's the finite quality of these products today despite the name on the tin.
Even Ohlins I'm afraid now that all these have become commonplace.
What you pay for off the showroom floor with the lush name stickers is, Johnny Walker Red. What you need/ want/ desire is Johnny Walker Blue label...
..and for that Sir, that'll be xxxxxxxx$$$$$$$$$ extra.
I suspect you Tim, like me, well, we're chaps of a certain age where the thought of Ohlins and Brembo was the Holy Grail...now...pedestrian.
Next shelf up Sir is what you want....