there are so many brands and so many variations, i had good VOLCANO Atomizer die after just 2hours ( very bad for $8 ) and i had some last for months
cartomizers are same thing but depends how clean you keep them also, and what you decide to vape inside them.
there is so much to explain that i am learning myself, but they are sorta like computers --- you can build two different computers using the SAME EXACT parts and manufactures and one will blow up first before the other.
just remember when you vape, understand what you vape, if your
vaping flavors with oil or excessive colors they will leave build up on the element themselfs wich could if not cleaned regularly -- cause failure.
i am sure this applys to different USA vs CHINA liquids and the purity of the liquid itself
if your
vaping good quality
juice, dont let it over-heat often, and keep them cleaned --- they should last long time
hope this helps a bit -- these guys here can help more than i can even understand myself