FWB
N/A
They don't flare if you know how to use them. If preheated correctly, takes 4 minutes, they will not flare. During preheating I put the kettle on the burner. When the meths goes out I light the stove just as if it were gas. They are very easy to use. If you only want a mugful, the preheat will boil the water without introducing the paraffin.I would expect primus stoves, with the dangers of flaring, to be orders of magnitude more hazardous on a boat than gas. Even worse if you preheat with meths.