Availability, affordability I think are the convenience aspects, that and the stretchy sides fit many across out demographic. Designs are cool, I like the camo, and when I use up what I have I really like the new stripes on the L/XL (here's to hoping they'll have the dual leakguards). With them being a pull up, they can also be more discrete to wear around, especially in public or in places with non-ABDL, than taping up a full diaper, and it makes changing simple; slip up, slip down, or rip the sides. At least in my experience, I can get them to hold decent wettings, and if the mood hits me, even the occasional mess. That said, I think they hold more of a nostalgia too, for many I think we all were bedwetters and that was a time when we found out we had an affinity for being diaper lovers, but then it was trained out of us, and the first thing we used to get back into our proverbial pool was our gateway drug into ABDL; Goodnites.