Hide the cable where possible and plug it in to the cigarette lighter. That's what I do. I've used one ever since I was very nearly the victim of an obvious "cash for crash" driver on the M23. He drove on to the motorway from a slip road and jammed on his brakes for no apparent reason.
just for peace of mind i bought a space-saver. it fits in the storage space perfectly.contact admin, get the discount code and phone Holdcroft Honda. they delivered mine in no time.