So I recently picked a few Kanger Mini PT 3's, I usually stay away from dual coil tanks because I don't like to waste liquid and some of the people I know go through liquid like crazy with their dual coil setups, but of course their burning high amps and lower resistance with their mods (I'm not into that), but when I got the Mini PT 3's they came with the enclosed dual coils and I picked up a few extra figuring it always good to have backups for your backups (I have lots of those) however I'm now on day eight of using the same coil. This has got to be the longest I've ever used a coil without replacing it. I'm really surprised and pleased. I'm by no means a super heavy user but no where near a light user either. I use it a lot so I'm very impressed with these new coils. I sure hope they all last as long and this one coil has and it isn't the special one of the bunch, lol.