Okay, a little while ago I redid my slickness test between the 3 retail consumer level QDs: Meguiar's Quik Detailer, Eagle One Wipe & Shine, and Mothers Showtime.
I sprayed each product on a section about 1x1.5' on a vertical panel on a van that hasn't been waxed in a while, but still had a bit of something left on it. I tried to be as consistent as possible in application - I sprayed it on, spread it around, and waited a couple seconds before gently buffing it off with a fresh side of MF. Bottles shaken of course.
Then I spent the next several minutes basically umm.... groping the side of the van, furtively glancing around to make sure the neighbors weren't watching. :lol It took me a while to get a feel for the surfaces, wiping my hand off from area to area, but after a while and a second QD application to be sure, I could tell there was a subtle difference in slickness. The slicker surfaces were more resistant to "grabbing" your fingers as you pressed down on the paint. I took a long time to do this and went back and forth between the various spots several times because I didn't want my imagination to be a factor.
In the end, I concluded that Mothers Showtime was still the slickest of the 3, with EO Wipe & Shine coming in second and Meguiar's Quik Detailer last. W&S was fairly close to the Showtime in slickness, but still grabbed more easily, and Quik Detailer was noticably grabbier than either.
This isn't to say that Quik Detailer is grabby and not slick. Like I said earlier, I've found most QDs to be quite similar in terms of performance. All 3 products will make your paint feel nice and slick again after a wash. This is just the subtle differences in slickness I've noticed at the limit, and one of the reasons why I prefer Showtime. Local availability helps too.