Rebuildables are not 'all that'.
If you are buying your juices and are not going through excessive amounts of heads and cartos, you need never do rebuildables. It IS more work, and not for everyone. But some people like to tinker, some people like to control their vapes, some people like to do a lot of dripping and thus head changing, and some people make thick gloopy juices so go through tons of heads and cartos, so it's cheaper.
But I agree that most people are probably happier buying cartos and heads

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