It's essential you prepare your herbs with a grinder for vaporizing. Breaking up the herbs increases the surface area exposed to heat, allowing vaporization to happen easier. Ground herb also fills vaporizer chambers completely. But it's important that the herbs not be crushed into a mass that doesn't let the heating air through.
Our original grinder design features blocky teeth that don't crush herbs while they cut.
We have always been impressed at CNC metal grinders that took the place of Sweetleaf and other early brands more than a decade ago. The biggest issue we had was the use of knife shaped teeth that weren't friendly to fingers and didn't cut as well as they should. We realized the best way to grind is not by trying to "dice" the herbs with a knife, but to sheer the material as scissors do.
This VB grinder is an older more simple design than Santa Cruz Shredder, which we prefer, but that company stopped supplying resellers and is dealing with pandemic related supply shortages. We hope they come back soon, but in the mean time this grinder is a great value.