yeah, they are pretty tough.
helll...back about 95 the guy that did my first v8 exaust sytem GAURANTEED that system would outlast the truck.
15 years later i found out the reason for that is because of where we were wheeling back at that time they called my truck slinky. (trucks name is really "pig" though....kids named it) anyway, he said there is no way in hell a frame could take that very long. the was i abused the truck it would be a goner in short order.
he told that story to me after my daughter who had not even been conceived at that point pulled his bronco out.....twice while i sat at the corner of the boggs and watched..
to put what it is to be a slinky in perspective....with over 2 inches of clearance for the fan.....when twisted up i was still killing radiators on occasion.....i fawked up a few radiators with the stock 2.9 setup.