Anything wrong with this??

"IF" a jack or both fail, then it would simply drop down to normal driving level, so kids underneath (don't parents watch their kids anymore? This is a driveway, not a campground) would not be "smashed" (unless they are under an actual wheel), although they might get a headache The pressure on those jacks is close or equal to if you raised it till just before the tires lift, which I'd be willing to bet is done all the time by many of those that are now claiming the sky is falling. As long as the brake is set (and operational) and the rear wheels are chocked, that RV is more stable than if it were sitting on all wheels with no jacks down. I will admit, though, that I would place a couple of blocks under the front wheels if it were to be sitting in that position for more than a weekend or so, just to lessen the long term pressure on the jacks.