I asked the company infotronik for the touch foil, the answer was:
the problem with the touch foil: the mirror contain metalic components which would cause problems using the touch foil
the problem with the IR frame is that it can’t be used behind the mirror
so i thing the best solution would be the IR frame… but in some forums I was reading also that with the mirror can be used either a touch foil or the IR frame… hmmm, now I am confused