not saying the substance is incorrect, just saying it makes it a real bu**er to removeThere is nothing wrong with the stuff they have used. It's just a generic PU adhesive used widely in the industry.
Infact the local vauxhall dealer used to bring me their cars which needed the factory option irmscher lower skirts fitting. The kits were all supplied with this type of adhesive.
I know it doesn't really bode well for making things removeable, but in general, the only time they are removed is if they are damaged for some reason.