Hypalon is pretty bomb proof stuff, and should last you many, many years, same with Achilles boats. But, I can't help throw in a different suggestion. When I hear "barb wire fence" all I can think about are Aire rafts(all I think about half the time anyways). The reason I think they might be more applicable for you is because they are by far, hands down the easiest and fastest rafts to repair in the field. they have a welded and stitched(NO GLUE) pvc outer skin that holds the shape of the boat and provides abrasion resistance, and a eurethane innner "bladder" that holds the air. The bladders are all fairly easily removable and replaceable( most for under $300 each, usually 3 or 4 per boat in the main tubes). You can carry extras with you and if you get a hole in one, replace it with a new one. But, even better than that, most bladder punctures you can repair with duct tape, and the outer skin you can zip tie or sew up. check out the aire owners manual;
page 13 gives a quick rundown of short term field repairs.
A hypalon boat will probably last longer in the long run, but there is no way you can patch one with tread and duct tape-they require glue and time.
Although.... I have always wondered if you could put an Aire cell or innertube, or some kind of cheap inflatable toy inside a torn hypalon tube, sew the tube up, blow up whats inside and limp down river. Anybody else ever done this or thought about it? I must be a genius or an idiot. Anyways, I hope this posts helps rather than hinders.