I used to do the lung inhale with cigarettes, but after 2+ years vaping if find it practically impossible to do now. Lol. Seriously, I just tried about 10 times, and my brain doesn't want to let my body do it. Okay, I finally got one, and the flavor is definitely less than a mouth inhale.
A contractor came to my house a few months ago to give an estimate on redoing our guest bathroom, he was a smoker and was interested in my ecig (provari, he'd never seen one 'that big'). I got a tip and let him try. He started inhaling as I was explaining mouth vs. lung and took this 10 second monster toke straight to his lungs. He nearly fell off the chair, with tears rolling out of his eyes. I felt terrible. I hope I didn't ruin him on ecigs forever.