Manuel's.
Unless you are stuck on the idea of using an e-cig like a .... and expect to have it dangling from your mouth I don't see a reason to go with auto batteries. You can get auto's for e-cig's that are way to large to dangle without hurting your teeth. Don't see a point to that. The manual batteries are less complicated and less prone to the risk other's have already mentioned of damage if juice gets into the battery and auto sensor. Seems to me that there are way too many things that could trigger auto batteries, especially at this time of year: house fans, high winds, open car windows etc.
As a noob I went with manual batteries and have no regrets.
Rick