The Barker VIP 3500 electric tongue jack was the best thing we bought. But our camper is 35' long in total length and has a GWR of 11,000lbs.
We bought ours online at AdventureRV.net. It was easy to install. Basically hook up the trailer to the TV and remove the 3 bolts holding on the old jack. Remove old jack and install the Barker with 3 bolts. There's a wire that has a raw end. I guess the hardest part was buying a connector for the raw wire that fits over the post of the batter and clamping it down.