I leave mine on for hours on end. Most I have ever left it on for has got to be around 8-10 hours.
Oh and I wrote a while back that I cracked my elbow on my whip extension. I ended up taking the extra glass nozzle for the bag and inserting one end in to the tube of the bag extension and the other in to the whip. There you got you got a universal elbow piece haha.
Not only do I like that I can still vape with the whip... so much more efficient I think, but I also have all that honey only collecting on one elbow instead of too. Only got to clean 1 instead of two when I want to collect all my honey
Also a little note on temps. I have run my E as low as 175 and still got vapor. I still need to try lower temps, but I was getting vapor at 175, my lowest temp I tried so far. It was some flavorful vapor too. For bags, I usually like to start it at 185, then 190, 195, 200, and depending on the strain i go for bag 5 or 6. But I can always get 4 solid bags out of whatever I got. Gonna be cooking soon with my vape poo, got around a half o now. Gonna put that in with a quad or so of some dank and make a batch of cookies. Haha wow, nice and sidetracked post.