I have biffed my Spinn BMJ (not from using a bridge hammock - from clumsiness). A 3-4 inch circular hole and a 1-2 inch circular hole. Patched well with GE II silicone and a piece of scrap Spinn.
A hiking buddy of mine also had a 1 inch hole in his Spinn from an acorn falling through it. (A physist hiking buddy of ours calculated the speed of the thing later that night around the camp fire - from what I remember 80-100 mph falling from 40-50 feet up
I was originally bummed about it, but the more I thought about it, the more character it adds (and the confidence I built repairing the thing was priceless in the event something happens of this nature again).