yeah the polo and gti badges will be stuck on! best thing to do i found when i did my rear badges was to heat the area first (as polosilver said

) and this makes the glue that holds them on looser!
then get a bit of dental floss and put it behind the badge and move it side to side in a sawing action and this should cut thru the glue.
any glue that is left u shud be able to rub off and then u can clean up the area with polish, t-cut, and even bug and tar remover!
hope this helps