Well,.. I've been reading about it for ages, and been learning from the pioneers of DIY hot (Thank you Mr Solubility!),.. and I've finally decided to take the plunge.
My heater is ordered, I've a registered gas installer lined up to fit it in my van, and I'm even getting a logo designed for the vehicle livery to promote the new "HOT" system!
The costs are actually surprisingly small so far,.. especially when compared to a branded hot retrofit,.. but I've still a few more bits and pieces to buy.