FWIW, again, Suzuki Genuine Parts KOYO u-joints seem indestrucable. I can get them from the dealer for under $40, with a dealer discount. If you talk Zook to the parts manager and how you use (read: break) parts wheeling, most will give you the shop discount, which is usually 25%, which goes a long way at making SGP affordable.
I've seem quite a few joints blow, both greaseable and non, but honestly the only thing I've ever seen blow a KOYO is uncontrolled axle wrap.