I pretty much exclusively use a healthy rips fury 2* (dry herb vape) now and I only go through less than a 1/4 a month with frequent usage. it's been wonderful for my wallet and for my lungs.

I can usually get two to three sessions out of the same tiny amount of weed at increasing temperatures and then store the vaped remains to make edibles with later. the efficiency is incredible compared to smoking it (even if you're trying to get super high and max out the temp from the start)

*their new product, the Fury Edge, just came out and it looks even better ( https://www.puffitup.com/Healthy-Rips-Edge-Vaporizer-p/hr.edge.htm ) . I can't recommend healthy rips' customer service enough either. I broke my first fury 2 by being an idiot and forcing the glass piece attachment (it works even better paired with a bong) in before the oven was ready and they still honored the lifetime warranty.