When I started vaping, I took about 3-4 second mouth inhales, then drew into the lungs, then exhaled a little through the nose, and a little through the mouth to get the most flavor out of my juice. Did this on ViviNova's, EVODs and the like. (I'm a fan of GrimmGreen's term "mouthal hits" that he coined for this very phenomenon. Still makes me giggle.)
These days I'm taking direct lung hits, and I think that has to do with the fact that I'm pretty much exclusively vaping either my Zen 2 carto tank (can't make enough pressure with a "mouthal" hit to keep the carto full), or my HH 357. I take longer toots, usually around 5-7 seconds. I noticed a great increase in vapor production and flavor, and also a much stronger nicotine "buzz". In fact, it's caused me to drop from 18mg to 12mg.
I have a Z-Atty on my radar, and I'm sure the lung hits will continue once I get into the open draw of it.