i used to work at kwik fit many moons ago-if you show the manager or super visor the wheel before they start the puncture that the alloy is unmarked you should be ok
Think it is a bit unfair to tarnish them all as bad---when i was there me & the manager changed tyres on a lotus charlton,we knew one little mark on the alloys & he would claim against the centre,took us from 2oclk to 6pm on the car-we normally shut at 5pm on a sat,the job was slow but the customer didn't mind as long as we didn't mark is wheeels