Review on SHIMANO Ultegra RD RX800 Rear Derailleur by Blake Pudic

I got the new one with a new bike and in the first 500 miles the derailleur broke in half. Luckily it was still under warranty and I got a new one. My other bike also had an R8000 RD (short cage) and the inner part that houses the spring broke. This was out of warranty but hardly used. I know nothing lasts forever, but my old Ultegra 6800 RD has about 15,000 miles on it and is still running after a couple of crashes. My 2 new Ultegra rear derailleurs never broke and didn't last long with a lot less mileage.