Which thick inert disc has higher quality to it?

[RibbedFlank]

*It might be too complicated for some to replace the ceramic flame filter on the VG with a Health Stone or 7th Floor ceramic flavor disc, but swim's cat wants to hash this out.

There are three discs I've found that are can be vaporized into and can be used as a flame filter: Health Stone, VG, and 7th Floor. I want to know which one is the highest quality, since I will use it as inert porous vaporizing pad and I am thinking of replacing the VG flame filter with one of the alternatives. Sizing can be reduced to fit into the VG, specifically the GVG Sherlock.

 

[Entheogenerator]

Haven't tried Healthstone, but VG's ceramic discs are of a much higher quality than the 7th Floor Ceramic Flavor Disc.