It's really hard to comprehend the differences without trying it, my friend.
I'll try for glass and zircon
I got glass and zirconia and I like both the same honestly. Also plan on getting other materials to try out.
For glass I feel like i need more cooling from the stem, while for the zirconia I feel like it doesn't need as much cooling.
I have to inhale differently depending on the ball+stem combo and because of the effects that happen along the way (me getting HAF) it is really hard to explain the real difference besides what Brenyo put on the website info.
As far as I can personally tell, the taste or the extraction/effect isn't affected by the balls type.
Cleaning seems to be harder for glass (if you use torching) but haven't had the courage to try it yet.
If you want to heat it up faster - boro glass
If you need it to be smoother/easier on the throat - zirconia
If you need a longer, slower session - zirconia
If you want a fast but rich and powerful hit - boro glass
I imagine steel balls should be like "zirconia+" and silicon carbide balls should be like "boro glass+" or "zirconia-" if you know what I mean.
As I put together another tempest to be for glass only I use them interchangeably all the time, can't really pick a favorite yet. Maybe I need more time
DAMN - became a wall of text...apologies...TLDR is smth like: "I like zombies"
Cheers