John, I just posted a response on one of the other web forums to a similar topic.
I have had Dave's wheels (both 80 and 180) for a couple years now and really love them.
I agree that they take a much lighter hand than with AO wheels to keep from going through a tool much faster than you are used to.
I think these wheels come grittier than labeled, and soften with use until they stabilize at the advertised grit after a few months. This is just my opinion though.
I can touch up the edge on my gouge or scraper faster with these than with the AO wheels. No dressing, and with the Varigrind jig, I just have some lines on the rail to quickly set up the distance depending upon the angle I'm using. Never have to remeasure, because the wheels don't shrink with use.
I like the combination of the 80 grit CBN wheel and my Roborest platform. I use that for most sharpening needs, and only use the Varigrind on the 180 side for reshaping gouges with side ground wings. The finish I get with the coarse CBN wheel is superior to anything I ever got with my AO wheels. Also, with the newer high vanadium and hardened steels, I feel like my AO wheels took forever to sharpen. Not so with the CBN variety.
I do think there is probably some greater familiarity with AO wheels for those who have been woodturning longer than the average. I believe that, if you are used to AO wheels for the last 20 years (for instance), there's likely to be a greater sense of "boy these feel different", than for those who have only a few years experience (like me).