I switched to glass for 306 and am never going back. You can get plain glass at TheEcig for less than ten bucks, and a lot less than that depending on what sale is running. (They just did a 30% off sale a week ago.)
GoodeJuice may still have some glass in Clearance but last I looked the color choices were down to black and cobalt blue. Only $1.99 though.
Only down side - you will break them. Poop happens.