I haven't used kerapremium, but I've used both the original QOD, QOD organiq, and Coppola.
My end-point is this, use anything but coppola. Initially great results, but 2 weeks later significant hair shedding.

Then I did original QOD (which kerapremium with formaldehyde is supposedly similar to), I had good results, still had some shedding (which may have been continued from coppola.

Now I maintain on QOD organiq and I'm quite happy -- safe and formaldehyde free, not as straight results -- but clearly my wimpy hair is sensitive to that.