As XfooYen mentioned, the AW IMR batteries and Xtar WP2II charger are great buys... Safe batteries, and safe charger.
No offense to anyone that likes them, but I would steer clear of any battery with "Fire" at the end of the brand name...
Trustfire, Truefire, Ultrafire, etc...
I've seen reports of these batteries venting themselves into PV's... Not good
In addition to the AW, I can strongly recommend Efest IMR's. All testing and comparisons suggest that the Efest batteries and AW batteries are neck and neck in performance, chemistry structure is the same, and the Efest batteries tend to be a tad bit cheaper. You know, if you're interested in saving money
Also of note... If you EVER intend to buy a ProVari (You may not be interested now, but you can change your mind later...) you will want to make sure you get "Button Top" batteries as opposed to "Flat Top"
The construction of the ProVari circuit board prevents flat top batteries from functioning (The positive terminal of the mod is recessed into the board)
That way you can use the batteries with the ProVari as well...
If you do plan on going against the advice of your peers and stack 18350's in the Vamo, you will need to get flat top 18350's... Two button top 18350's stacked will be a little too big, and the bottom cap / battery cover will not thread on all the way.