No scissor jack is ever going to be perfect. This is because scissor jacks are imperfect things. This is science. However, as far as imperfect things go, this one is about as good as they get. So if you want a scissor jack, this one will probably be just fine for you. I only gave it four stars instead of five because scissor jacks can't ever be worth five stars. Science.
I haven't used this to to pump a vehicle off the ground, nor is it likely that I ever will do; I didn't get it for that. I built it in to a router table for my grandson to make raising and lowering the router itself as simple as possible. And for that job this particular jack works perfectly well - it doesn't sink under its own weight so once you've got the blade depth sorted that's it. Done job. So it fully meets requirements.
Clearly this model is ideally suited for light work and is a very cost-effective piece of equipment.
I'm happy with the thing. Considering it's a scissor jack...