When a canopy fabric is torn, it tends to go all the way (from nose to tail) with ZP fabric. With F-111 fabric, that is much less likely (it is gonna stop). I think it is important, taking into consideration that it is your LAST canopy. Also, ZP pack larger comparing to F111, and that may make you downsize just to make it fit into your reserve container. Again, not a good idea, in my opinion. And, as mentioned, ZP is more difficult to pack. Bart