If you're a flat lander or don't have to change gears much Quad-ranges are ok, if you're on hills and/or varying loads and speeds are needed, the Power shift works much better.  On hills, QR's suck, for turning around pulling and or lifting equipment while turning !   On flat land you can idle down and creep while turning around.   On hills you'll be lucky if the engine only quits and you can get the tractor stopped.   I've seen what happens when you're NOT so lucky.

Only mistake JD made was not going to the 15 speed Power shift back when they went to the old school 30 series tractors.

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