Looks like a beast, performs like a pusscat. I do reckon though that if Joyetech made a lower ohm coil for it, perhaps around 3 ohm?, then it would perform like a champ. I put my Cleito tank with a .27 ohm coil in it on the Unimax 25 battery and it worked quite acceptably. Nice clouds and good flavour. Easy a 60% + improvement over the Uni tank with its .5 ohm coil on its own battery. Not quite the full experience the K4 gives but real close. The cleito tank on the K4 battery was a tad less restrictive on the inhale when compared to being placed on the Unimax. Im thinking the coils for it are not a percect match for the battery output.The Unimax starter kit is a let down.