The HDvapes are pictured on their website as having brass screens.
Brass screens are produced in the devil's basement by his soulless minions of the night. They have no benefit over stainless steel that I'm aware of - they taste like crap, they disintegrate easily (mostly into your lungs, mind you) and generally piss me off.
Both stainless steel and brass often have coatings on them for whatever insane reason, probably so they don't rust while they sit on a store shelf for a decade. Before I use any screen for any purpose I hold it with tweezers while flaming it, watching that oil-slick crap disappear. Try using a high quality stainless steel screen which you've flamed.
Also give everything a salt and rubbing alcohol shake - the glass blower could of somehow gotten some crap in there and spoiled the taste. Hell, we should probably all give new glass pieces a bath before using them, both for sanitary reasons and because sometimes pipes have glass dust remaining, or even glass chunks - as someone who has blown glass for a bit it's not even something you can blame the artist for, it's just what happens when you're running production.
So in your experience, does the glass VG win out over the HD vape outside of the flavor issue?