Not very robust,
This review is from: 4.2KW Calor Gas Heater Portable Cabinet Butane Fire w/ Regulator & Hose Home NEW (Kitchen & Home)
I bought one locally as it was on a deal with a 15Kg gas bottle. This bottle virtually fills the entire cabinet and it is very fiddly to turn the tap on and off. My old heater had a little door in the top to facilitate this.
I have to hold the thermocouple (failsafe) button down for about five minutes or it just will not stay lit. Also if you walk past it quickly enough to cause a small draught the flame goes out altogether.
My machine was made in China and I think sometimes wholesalers import these things with an eye to a great profit margin when in fact they are cheaply made and barely fit for purpose.