I was happy with this priduct up until the point it broke, or seemingly broke. I had hardly used it, maybe 20-30 inhales. It started to taste burnt which I assumed meant the middle bit needed replacing (despite being so soon) and so I cleaned and replaced it. But still seems broken. So I reckon the vape I used (starter kit) is low end and bordering on useless, or i don't know what I'm doing and boredering on useless. I don't think it's me, it's just a vape pen with four parts, it's hardly complex. So my advice maybe just buy a better vape pen. The liquid side of things seemed fine to me, no complaints there. Unfortunatly 2 stars. I wanted it to work