It's a worthwhile add for people with joint problems. Slightly over five years ago an old rotator cuff shoulder injury acted up, irritated by the work I was doing. A couple years of physical therapy and two more years of gradually increasing exercises, and I've recovered
most of what my shoulder could do beforehand.
Cranking the landing gear on our Scamp 5er up or down was torture. Lynne had to do the cranking for me. Adding the electric motor kit made it so I could solo with the rig again. If you have shoulder problems, I highly recommend it.
You can buy this kit,
ATWOOD 5TH WHEEL JACK MOTOR KIT 75391, for around $250, but I bought the used motor off of eBay for $60 or so and bought a switch, switch housing, and wire from local hardware and car parts stores. The installed unit does not interfere with using the hand crank, by the way.