I've had them last anywhere from the second hit too two months. The QC sucks, it's a luck of the draw thingy. And the people selling them give you only an DOA warranty. If it hits once then pops, you bought it. Only defense it to buy them by the pound from China. Or, you can mess around building your own coils. I don't much care to even screw in another coil, let alone building coils. JMHO
Cheers,
otrpu