So I had an occasion to use my HumVee jack in a near perfect situation--swapping out a slow leaking left rear tire with my on-board spare. 2003 E250 EB weighing about 6500# as it sits these days. tire size 245/R75-16 on stock steel wheels, all work done on a flat paved street.
With the Agile adapter when raised the van felt solid, not a bit of sway, flex or scary movement while removing and replacing the tire(s). Even though this was my first and hopefully last time using this I'm convinced its so worth the money spent.
With the included tools its nearly effortless and mostly a one-handed job. Of course the lug nuts were/are another issue which I knew would require better tools than the angled combo wrench that's part of the stock/factory jack and handle stuff. FWIW I carry a 3/4" drive ratchet and 7/8" deep well socket which also works out quite well.
Storing all this gear is easy enough in my van as I have an unused space under a steel shelving unit on the passenger side---everything fits in an area about 6" wide, 10" tall and 30" long. Since the wheel well occupies most of the undershelf space it works out perfectly.
So anyway anyone on the fence about one of these should strongly consider one if you want to work safe when changing a tire. Given its benefits finding a place to store it should become a priority so it can be on-board when/if needed.
Here's a few still on eBay I'd suggest, no affiliation:
https://www.ebay.com/itm/M998-HMMWV-...kAAOSwp~pdYGxc (Missing some tools, available here:
https://www.ebay.com/itm/M998-HMMWV-...QAAOSwIVpdc6Vx)
Full Kit, fair price:
https://www.ebay.com/itm/HUMMER-H1-M...4AAOSwoRpcOQpF
Those are a few but not the only ones available--its best to shop around before buying one.
HTH