Well, we had a scary time with our tripod jacks, but then I noticed that one of them had been modified to break down and it was in fact bending and ready to break.... Ten minutes with the welder and I was back to original condition.
We have a 3/4 ton 4x4 dodge pickup with 33" tires and once the jacks were repaired, we had no issues whatsoever. I have 1" of wiggle room or less on each side. With two of us, we loaded the rig in under 15 minutes and did not feel unsafe. That is with a fully loaded Keystone 9.5'.
I was going to buy corner jacks, and had been watching craigslist for the last six months. But after a few times loading with the tripod jacks, I doubt I will ever change things up.
Regarding the tires rubbing the tripod jacks, yes ours did that but it didn't have ANY effect on the camper. Plus, by that time the camper is just going to fall onto the pickup bed.
Just my .02.