I got the medium cage version so I could run a larger (11 X 32) rear cassette with a compact double front crank, pretty much replacing the need for a triple set-up and able to handle all but the most strenuous of climbs. Works great, shifts smoothly, I don't have anything negative to say so far.
Built up my wifes bike so that we can travel to Europe. This new derailleur gives her a 34-32 ratio so that she can climb any and all hills thrown at her. Much better shifting and lighter than a triple.
Ordered the mid cage for the 11-32 cassette to place on one of my bikes for riding the hills. Once ajusted which took about 20 minutes, after watching a sram u-tube video, and one very minor road ajustment this deraillure has been smooth and quick. No failures of any kind during the first 200 or so miles.
I am more than pleased.
THIS IS THE SECOND ONE OF THESE I HAVE PURCHASED AS I CONVERT MOST OF MY BIKES OVER TO COMPACT GEARING. THE LONGER CAGE WILL HANDLE UP TO 32 TEETH IN THE REAR CASSETTE, WHICH GIVES ME THE CLIMBING OPTIONS I NEED WITH A DOUBLE CRANK. SHIFTS GREAT.