Think I figured out my distain for the Vivi.. The small one works great on my Ego style batteries the BIG one sucks on my LT and its not the Vivi its the LT.. There isn't a place for it to draw air.. I'm getting a MVP and VAMO for xmas and I'll try it AGAIN.. The mini Vivi got better as it broke in.. Now it's my best tank for my Ego batteries.
I have the Chrome LT not the 2.0 and the Vivi sits to flush on top..
I use the 3.5 ml Vision vivis with the Vamo and they work perfectly. I have another mod that caused an airflow problem because its centre post is a bit too low, so I just use a 510-510 adapter. With the adapter they work fine on that mod too.