lazylightning
It's an obsession but it's pleasin'
A tighter diameter air path will allow more airflow over the material. Too tight and your pulling to fast (Heating element cannot heat air that quickly), or too large and you have to pull that entire cavities worth of air (which means you waste most of your lung volume. When smoking your trying to fill the chamber by utilizing a syringe effect, in my experience with vaping (since the MiniVap needs constant pull) your trying to keep constant flow.
VapeXhale glass is designed with this in mind and that's why i choose them
I think this is why a piece the size of the Mobius Atom works so well as a vapor bub. There just isn't much to clear so it's more like a constant flow of conditioned vapor instead of filling a larger volume can and then clearing it. That makes it easier to gauge hit size too. And if you get a tickle in your throat, just stop hitting it...no need to clear a big can of vapor.
Of course, if a vaporizer has a heater with enough power to keep up with a fast hit (like the MV), it's hard to beat the satisfaction of a fast, hard rip through a bigger bubbler like the Mobius Ion or Clear!
I'm spending the weekend getting acquainted with my new MV, mating it with all my glass and testing configurations. Apparently I don't own a piece of glass it can't milk, even on blue!!