Such negativity! I got a Regatta heated coat for Christmas last year and it's awesome. Almost instant heat that you can regulate as you get warmer. It's really well insulated so you don't need the heat on for long, sometimes you can get a bit too warm. An added benefit is if you get the right battery pack you can charge your phone at the same time.
My top tip - don't put a packet of chocolate raisins in your coat pocket for that long walk....
My top tip - don't put a packet of chocolate raisins in your coat pocket for that long walk....