I'd keep it in the landy somewhere for just in case situations but this time of the year, and probably even in general you probably shouldn't need it. It will make next to bugger all in fuel saving to be perfectly honest, it depends on how you look at it. Risk over heating the engine or save a few quid. It wont over heat without it at the moment. Land Rover have to compensate for every climate in the world don't forget. It's not like your in the middle of the Sahara desert hard working the engine is it?
-Pos