I've run H&R spacers in both 10mm and 15mm fitments on my last 3 cars over a total of 50K miles without a single problem
I did actually buy some FK ones for my old Bora many years ago and sent them straight back for an exchange to H&R's without even fitting them as using my wonky engineers eye it was obvious they were far from the last word in quality... take a search over on the vortex and you'd send yours back too...
H&R's FTMFW