In addition to those mentioned here in the comments already, another problem that publishing through the Mac App Store is how buggy OS X’s sandboxing can be. I

In addition to those mentioned here in the comments already, another problem that publishing through the Mac App Store is how buggy OS X’s sandboxing can be. I don’t know if the problem still exists under 10.11 (I bet it does but I haven’t checked), but one bug that I’ve hit consistently has to do with file open/save dialogs. Open/save dialogs in sandboxed apps aren’t opened directly. Instead, requests are handled by the privileged powerboxd helper daemon, which then passes back user choices to the sandboxed app. This sounds great in theory, but something that happens somewhat frequently is that some part of powerboxd’s dialog initialization silently fails and doesn’t open a dialog, leaving the user confused as to why his requested open dialog didn’t open. Worse, when it happens, it can happen several times in a row, meaning the user can try several times and not get any kind of feedback whatsoever. It’s been a known issue since at least 10.7 and last I checked (10.10) it still hadn’t been fixed. This is a showstopping bug for many kinds of apps but it’s simply been ignored. I’ve been wanting to move off of the MAS but as a one-man shop, writing in serial code support, trial mode, and registration is daunting, not to mention getting old users set up with a new license. I might just delay the move away from MAS until the next major release.