Thats what would worry me, the number of stone chips I manage to pick up is rediculous, if it's strong enough to hold them off though I would be seriously tempted.
the vinyl acts a protective layer also and is very resiliant (spellcheck) to stone chips. He said they haven't had a car back for a replacement front bumper wrap yet.
Obviously if it did go through the vinyl or anyone scratched it you just have that panel re-done so hardly a big problem. If someone puts a decent scratch in your paint, you'll need more than t-cut anyway! Vinyl is guaranteed for 5 years and the fitment for 3 years.