Slightly Medicated
(SliM) Iron Lungs
The glass stem design...I love it! It has a little play in it so you don't have to worry about breaking it with a little adjustment. And if the rubber seals at the ends of the air path are working you will never taste anything but glass. I don't think tightening up this glass would be good at all...too tight and you risk easy breakage.
Battery life...I'll have to test this. The problem is that it has an auto shutoff that is motion sensitive, so I can't just turn it on and leave it there. Five sessions seems like a bare minimum to me. SliM is getting six sessions and he runs it on high the whole time. I think eight to ten lower temp session is very doable.
Like sticks said the glass stem design is good in my. You really don't want the glass scrapping against each other. You might be able to reduce airflow by reducing that gap. The manufacturer would risk making the device more fragile.
I would say I get 6-7 sessions around 10-20 minute each on high. I could probably get 8 if I pushed the battery. Running the unit as hot as I do will reduce battery life. I feel like for my expectations that is a pretty decent runtime for a portable.