Good quality. Well built. Reaches the needed temperature quite quickly. Battery lasts for quite a good number of uses.
The only con i found is that once it's on, the device maintains the heat and keeps vaporising whatever is in the chamber so you have to use it as long as it's on - meaning it would have been better if it had a button to tell the device when to heat rather than having it heating as long as it's on.
Not cheap but very good.