I have five of them and they all work great. You do have to make sure the coil tower base is seated tightly before you replace the screw on base. Don't overfill them, or they will siphon off juice, and once in a long while I get a replacement coil that scorches on the first use and once the flavor wick is scorched it never tastes the same. My guess is only one of the two coils is attached properly, but that has only happened twice out of 30 replacement coils. I use 70/30 PG/VG juice and start a 2.1 ohm coil at 8.5 Watts to break in a new coil, then bump it up to 9 watts on my SVD. It tastes great and gives me tons of vapor. Unlike other cleros I have it travels well and I even use them trout fishing on the rivers with my MVP at 4.3 to 4.4 volts. Yes, it does eat juice, but that is the price you pay for tons of vapor. They are easy to clean and easy to use, but if you scorch your wicks the coil is done as far as good taste so bump up on wattage slowly on your PV. I know that some folks use higher wattage, but they must be using different juices, different PG/VG mixes, and different PV's. My experience is that it is best to slowly bump up your power and when you hit a good sweet spot stop. If it starts tasting crispy or not as good immediately drop your power back down or you will ruin your coil/wicks. Once you scorch your wick your taste and vapor production go down hill in a hurry and the only cure is a new coil. Chalk it up to a $3.00 mistake because cleaning won't help you once your wicks are toasted.