Quartz is quartz
Quality comes down to the build. Many times it is OK to fuse a seal with quartz, but if you want quality, it must be welded, like the do with boro. The issue is that quartz melts at a higher temperature as well as creates a lot of bloom that has to be chemically removed.
Thickness does not mater in quality, other than the thicker, the better it can hold heat. It is also harder to make
our elev8 quartz terp typhoon and terp slurper both feature the best build quality with great quality quartz.