I'm going to go against the trend here,,,,,,,if you LIKE the small size factor of a cig alike, I'd go with the Volt 78mm size battery.
You can get them from Smokeless Image, they have many starter kits, and one battery will last you about 3 hours (78mm size). Personally, I like the larger volt, the X2 because of the longer batt life, but if you like the smaller size, Id just get several of them to switch,,,,,you'll NEED at least two batteries,,,,,,,,and they can only be recharged about 300 times,,,,,,,so the more you have, the longer they will last. I made the mistake of getting only two,,,,they lasted about 3 months, with several charges a day. I would recommend 3-4 of them if they are your only battery. They come in automatic and manual.
If you don't MIND something the length of a sharpie pen and the thickness of an AA battery, then the X2 might be for you,,,,,at least at home. The advantage of the X2 is you can use it as a pass through,,,,,,,that is, you can plug it into the wall and vape at the same time it charges (this will slow down the charging a bit, but you're not using your battery power doing this) as you're watching TV or on the computer. Then unplug it, and off you go with a full battery to do whatever you need to do away from a wall charger. A car charger makes this option nice as well.
There are 3 sizes of Volt X2s,,,,each one a bit larger than the next,,,,650 mah (about 6.5 hours batt life vaping) 900 mah (9 hours) and 1300 (13 hours).
Obviously, these need to be charged less often,,,,,,,,so the 300 charges would last much longer.
The Volt X2s also come in automatic (which I own and love) and the manual (button) which people also love.