I also have blue lights in door handles and pull recesses, power socket tray and central drink holder ... although I'm a bit concerned with your lighting colour association
This mat set has the lip, so yes, the footrest goes on top of it, the other set is the same shape as AMG, so no lip, and the footrest then goes direct onto the carpet.
Simple to remove in either case, as it's not glued/screwed/nailed or molecularly fused to the mat/carpet.
The velcro is a genuine VELCRO industrial strength low profile 91050 tape - no wobble, doesn't move, and certainly never comes off by itself.
It's much finer and shorter, than the usual generic velcro. I normally use 3M Dual Lock in the car, but it obviously requires both sides to be dual-lock, for it to work.