I plan on picking up the xhale o2 today pretty much as a disposable to see if vaping is a viable option for me. I know it comes with 5 cartridges, but from what I read, these aren't gonna last long. Does anyone know if I can top off the cartridges on this model? If so, I'm currently smoking menthol lights, anyone have recommendations on what is a good liquid to buy? I plan on using this until I can get a Joye 510, but REALLLY don't want to pay for the overpriced cartridges. Advice?