I've used AIR apps(as a consumer, not a developer) and there are times when I get a little frustrated with the experience. Still, I use the software because it saves me time and makes my life 10x easier. Overall if customers are criticizing your use of AIR as a platform rather than praising you for solving their problem, then you have bigger problems than the AIR vs. Native debate. Many users will tolerate even the crappiest of experiences, see IE6-IE8, so long as it solves their needs.