dual battery

I’m in the market for a mid to high end dual battery squonker. I’d be willing to trade my VapeAMP rig mod. It’s got a few signs of use but nothing crazy. No single battery or mechs.

I'm looking to buy a new squonker. I just bought a wasp nano and I want to squonk with it. I have a geekvape s100 but the 510 pin is too short for the nano. I prefer dual battery mods for the battery life but I'm open to suggestions. I also like the look of the hcigar aurora if someone is...

I apologize if this has been beaten to death, but I am looking for some answers on what dual battery configuration is supposed to be more efficient. I'm looking specifically at regulated mods... I have both a Vapor Flask DNA40, and Sigelei 150TC. The VF is parallel, and the Sig is Series...