The vignettes are virtually impossible to remove in one piece - unless you take action which requires a degree of planning and would be illegal.

I'm with the others who think that for a rental to drive in Switzerland, too much planning is involved if renting in France except in certain limited circumstances including good knowledge of the non-motorway routes.

I rented once in Germany, close to the Swiss border, on my way into Switzerland and the rental agency had a doctored sticker which they stuck on the windscreen and presumably peeled off on the return. All highly improper, I think.

Very OT: the German language satnav voice changed at the border from one with a German accent to one with a Swiss accent.