To be honest, while I know that some people like the smaller size of disposable mods, I learned quickly that such mods while some can have a decent lifespan, once the internal battery is dead, it's a paperweight, which is 1) wasteful, and 2) once dead on the go, you have to recharge it and can't use it during this. If you really like your mod, it's sad to just see it end up seeing it going into a recycle bin.
The replaceable batteries type have become much better, some models are very small now, you can carry spares to switch on the go, those batteries can be replaced so the mod is good until the chipboard dies on it, getting another battery or two is much cheaper than another mod, and if the mod does die, you can simply get another mod and still use the same batteries which ends up being much cheaper.
While I know that this doesn't answer your question, it's just food for though.