Reviving this old thread because it's one of the more useful I've run across. It helped me decide to get a jack (and this particular one after comparing to the less expensive, but not as robust versions out there).
My girlfriend and I ride Mountain Max. True they are not exactly heavy, but when it is just her and I, there is only so much strength available for yanking on the back of a stuck sled. We've owned this since mid season and finally ended up using it last weekend and again this weekend. Prior to that, we were able to get out of our stucks in typical fashion, stomp down leading snow and push out, but this time, that was a no go.
First time using it it took about 3 - 5 minutes to pop the back out and put it down next to the trench (including photos). Five minutes later, used it again. Really takes the time and effort out of getting unstuck. My back isn't 100% and I just can't see risking hurting myself when there is a tool that will do the work for me. And there are those awkward stucks that even if we are both giving 100% that our combined strength just wouldn't be enough. And even when it is, panting and sweating after 20 minutes of shoveling and yanking at 9,000 feet just means that much less time riding and physically wearing out earlier in the day.
I used it again this last weekend when a buddy was in town and riding one of our sleds. He slid down into a treewell and we jacked the front and back out and up to get the sled up far enough to ride it out.
We ended up ordering one of these after we worked on getting unstuck for 30 minutes one day in the middle of the season (wasn't deep, but sidehill stuck and hung up on a stump and we had to lift the sled high enough to get it over the stump). We'd been considering a jack for a couple weeks at that point and as we sat there frustrated, the $300 seemed much more reasonable. We ordered it when we got home from that trip.
I've no experience with the more economical versions (PowderJack, etc.) but I only have praise for the Highlift Jack.