I'm not sure how I did it, but I've managed to vape 20+ml of Boba's without having to re-wick and clean the coils. I've never had that kind of results before, with any build, in any atty! The most Boba's I've ever vaped cleanly is probably around 10ml. My guess is the coil is staying good and satuated, so it's not burning and gunking it all up?...(dual 28ga x 2.2dia x 8 wraps, .69 ohms, regulated 20watts, lots of cotton sitting on the deck only)