There is a huge variance in quality from every manufacturer out there. I've got 2 510 attys my wife has used for over 4 months now that were "cheap knockoffs" and I paid $2 for them. I'm staring at 4 blown up Joyes and 2 dead boges just from last week on an order I placed. I have one cisco 306 I have been drowning for 3 months, and it still tastes fantastic, never cleaned it. I have the 2nd cisco 306 from the exact same order that didn't last a week. I have a few differe Ikenvapes that lasted a long time, next order I placed I had 2 that died in a day.
It's frustrating, and horribly random it seems. Cartomizers are a tad bit better in that they cost 1/5th as much as an atty, so those just hit the trashcan. It is the same experience with those as the attys. I
vape 6ml a day though, and I tax the hell out of them. My wife just vapes her little pink ego 2ml a day. Maybe I could get hired to Stress Test these attys/cartos for everyone... or at least get a discount on my second order since I already did test pretty much everyone of them out there.
They are ALL made in china, you win some, you loose some. Find a vendor that at least lets you mail the DOA ones back.