Finish line is much stronger than design line although not as good going round sharp corners. It’s virtually impossible to break with your hands without it cutting into you like a cheese wire. Design line on the other hand is great around corners but can snap quite easy. I always make sure that I have released the wire from the tape at both ends before applying the vinyl. Your probably aware but when going around corners try to avoid stretching it, less chance of getting a badly shaped corner. Had this bike in for stone guard and used knifeless tape for the majority of it.