I think you tend to miss some of the other stuff (CBD/CBN) and get mostly THC when you vape.

My Volcano will get me 'high' - but my Bong will get me 'stoned'. Even with the same herb you can get a very different high imo.

BUT - after using the Volcano for over a year now I can honestly say that you build up a tolerance to it very quickly. Especially if you are using fine ground herbs, sometimes I take a break and get some bong action in too