insurance is a bugger..............and i am a bit sly regarding it.
i built a steel mounting place to which everything is mounted, its secired to 2 bolts already on teh car and i carrya spanner, which means its off in 2 mins if need be then thrown in a bush.
worst case, disconnect it or dont carry a bottle all the time...you dont use ti that much after the novelty and mostly when you plan to use it its more exciting.
dunno........this insurance thing is so hyped up but its not illegal, you dont really need stickers.