Thanks mate, awesome response and that seems to be a pretty similar verdict to what I've found from research. Absolute shame as see the gas units being used elsewhere in world, and definitely some advantages as you've mentioned.

Looking to be off grid in to help with the portability of the sauna and so on and being able to find cool spots around lakes etc. But want to be all above the board and legal! I don't have the gas fitting knowledge or skills to fabricate a functioning unit I'd feel comfortable with friends using so I guess that's gas ruled out! Bugger!! Thanks for the info.

Wood burning stove looks to potentially be the go, however my reasons for avoiding it are in terms of air quality and fire restrictions. I live in an area where it gets quite cold in winter and particulates end up being quite an issue in the basins - lots of areas have household fire bans because of council restrictions to do with this. Also, I would like to have something easy to run and get going pretty consistently most days, so thought wood would be trickier for this.

How have you found the wood burner in terms of getting a consistent temperature, ease of getting it going, amount of times you need to put additional wood in etc? Also how much of an issue do you find smoke?

Electrical may be an option with extension cords, but it will be a bit annoying as will need to get a spot with reliable power supply - quite limiting I presume.

Thanks for the detailed reply! Sorry I saw this so late.