I haven't tried the VG, but from other people's experiences I have read, I would agree that it is somewhere below the GVG and The Machine. My experiences with the GVG and The Machine are as follows:
The Machine: 6/10
I agree with endless (as usual

), in that I don't like the idea of using copper/stainless steel mesh for vaporizing spice. That being said, I have found The Machine to be incredibly easy to use. I was never careful with the flame, putting it right up against the steel mesh, and pyrolized DMT was never an issue. Thoroughly melting the DMT into the stainless steel mesh ahead of time allows the mesh to act as a buffer, blocking the flame from touching 95% (rough estimate) of the DMT. The vapor produced was never very harsh. In fact I would say that it was only slightly more harsh than that produced by the GVG, if I remember correctly. The biggest problem I had with The Machine is that the glass would often crack after 3-6 uses, so even though I was and still am an infrequent DMT-smoalker, I felt like I was constantly buying tiny glass bottles and drilling holes in them.
GVG: 10/10
After trying
a lot of different vaporizers for DMT, the GVG blows them all out of the water. As far as I can tell, it does not get better than the GVG with a ceramic disc.
Adjhart wrote:After all my research I'm probably just gonna bypass all of those and make only enhanced leaf/changa.
It just seems like everyone who tries it prefers it.
Many people do prefer enhanced leaf/changa. I have limited experience with both, and I still dabble with them from time to time. But I personally would take vaporized DMT crystals or vaporized DMT crystal/ harmala freebase over enhanced leaf or changa any day, by a long shot. One of several reasons for this is that I prefer to avoid inhaling the smoke of burning plant matter when I can, even if it is just a small amount of inert herbs.