i have used bags since , 92 , yes 12 yrs , on 15 or more cars . only 1 car has ever busted a bag and that was a installer eror .
if set up correct they will last for a long time and many miles .
i have put them on 1 ton tow trucks and used them for 80000 miles towing cars , never a problem .
so dont worry about them failing.
the ground is the limit