Hi-lifts are a great last resort option, but I've always found them terribly dangerous when not on a completely flat, stable surface. Too many time's I've been out on a trail and had a vehicle up on a Hi-lift to swap out a flat or do a repair and you can just see that thing wobbling or you can't get it to quite lock in to the next hole. Fortunately I have never seen one actually fail, but I've heard stories. Plus, unless they are stored in a case or bag, they invariably rust up and then they get really tough to try and use. Personally, for home use I'd stick with a standard floor jack and for the trail I'd get an exhaust jack like this one:
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Yeah, they aren't cheap, but you pay for what you get right? And they are awesome.