I own the whole copper
vape jam set up and i have to admit, it's very nice. Low voltage drop (.3 on a .3 dual parallel coil) and it's solid in the hand. I do suggest that you do NOT mess with the bottom end cap at all, as you run the risk of stripping the threading and making it a pain in the ... to work with in the future. Unfortunately,
vape jam's customer service doesn't really exist, so tinker at your own risk. All in all i'd say pull the trigger if you're looking for a nice copper
mod and want something a little different than what other manufacturers are producing. Happy shopping!