In my opinion, Glass...It's just a cleaner vape.
I just converted to Kanger tanks (Pro, Mini, and now Pro 2). Used to have nothing but Novas. But the taste would be off after some time. The acidity in the liquid will do that if left in the tank for too long. Since going with the Kangers, I've never had a bad vape, even if I left the liquid in there for over a week.
cleaning is a pain tho on the mini and pro...but just waiting to get my proII's in.