heh, I know what I am doing with coils mostly, I know about coil killing juices etc... I'm using a premade, I'm trying a better build with my lone rba(hubby is actually using the other) I have for my pro tank, so premade in.. and I know if I get more than 4 days out of this coil I'm going to be damned lucky. why? I know this juice is sweet as hell, it's raspberry cotton candy and ohhhh so damn goooddd! I was changing the cotton every 4-5 days on the RBA, because I'm vaping 10 -15ml of it a day and the cotton and coils were a disgusting black/brown leaking gunk into the juice. what you vape and how much of it, is going to dictate how long those coils are going to last... I have some juices, yep I could definitely go a few weeks without changing a coil, they're the odd ones since I have a serious sweettooth with my vaping.