The math really doesn't check out on them, for the price of just two of these you can buy a bottle of vape juice, and a replaceable pod based vape from a company like OXVA. Once you've bought three that covers the cost of more pods and more juice and you're set for way longer. Still kinda bad since the pods are technically disposable but they last longer, they're far smaller in size, and they don't have a lithium ion battery. I see people buy these things for convenience, and I admit I did once when I had lost my vape and was waiting for the replacement to come in. But I can't imagine throwing an entire device away every month or so.