Just got one of these, so thought I'd add a somewhat noob perspective to this thread. I have the 2017 RideEngine. Had a hook spreader on that one, got the rope on the stealth, as I have no plans to unhook. I've only used it twice so far. Because of the extra padding top and bottom, it is 1000% more comfortable than the RE spreader. I didn't even realize that was an issue until I put this on. So far I like the rope slider, I barely notice it, other than it feels like my bar is slightly farther away. At some point I will replace my chicken loops with smaller/surf versions. Folks with way more experience than me used to the stationary hook will probably be more attuned and notice a difference in the way it moves. I liked it for topside strapless, but I'm still working on turns, so I can't blame falls on anything other than inexperience
I'm still fiddling with the fit. A bit of a pain, as the RE 2017 strap only has one strap on each side that circles back (not like the double straps on 2018), so it has to be fed through both holes on the stealth. It pinches a bit at those holes as it's fed around, so making adjustments involves taking it off and working it through. Shouldn't be a problem any more once it's all fit and broken in. The click in is super nice, very quick, and feels solid once you hear the small click. I have to make sure the rope or ring doesn't interfere with the latch (small thing to check, get used to it quickly).
Not stealth specific, but handing kites off to friends is a bit of a chore for obvious reasons.
So far this makes a great harness even better.