Airy draws have not been a problem for me, and all I use is manuals (PTs and batteries). At least not that I now know of. I did have a carto that I rinsed last week, which turned out to 'seem' like 'my' draw was too airy (relative to vapor output), but then I measured it and it was way over 3 ohms, I can't remember exactly, maybe 3.6 or 3.7 so I just threw it away.
Manuals are also better (imo) because when I want to, I can push the button one or two seconds before I even draw from it. Some people have posted that you can't draw like the way you used to with a cigarette, but I often do it many times. I don't know why, maybe I have the right flavor at the right strength, and learning the early button trick.