Ok so took off the lid and tried without the o-ring. Really don't find any difference in draw, just keeps the stems snug in place. Here is the pic of the cap off. Not sure how it is supposed to look though.
http://imageshack.com/a/img547/5814/pb51.jpg
Compared to Tom Funk my unit is definitely off.
Level 3 - zip/zero vapor
Level 4 - tiny tiny amount of vapor, good flavor
Level 5 - slightly more vapor but unless blowing into a light you can't see, still good flavor
I always just put on Level 7 - small cloud with a long pull vaporbonging (less with dry stem), always good flavor
I just finished one pack in the GonG through my bubbler which is bigger than the water tube (I wanted to see how much vapor I could pull into the piece). Started it on 7, heated super fast still (35sec or so) so I let it sit for another minute. First 3-4 pulls gave very little vapor, mostly flavor hits. Kept taking pulls until the timer shut it down, last pull seemed to get better. I turned it back on and took about 5-6 more pulls that definitely started to milk up a bit and flavor was perfectly fine throughout. On the last couple the vapor started to drop off to almost nothing again so I emptied just before the 2nd timer shut off. Here is the ABV.
http://imageshack.com/a/img855/5128/c1t4.jpg