I bought one of the Maplins heated vests just out of interest, as they were down from £29 to just £19 when I was at Teeside Park the other week. I thought at that price even if it was crap it was no great loss so worth a try.
They only come in one size so the major heated clothing company's advice re fitting, ie close fit near to a base layer can't be applied in this case. They work off two battery packs, each taking three AA batteries, and don't have a plug for fitting to an outside source such as the bike's ancillary socket. The battery packs are situated in pockets on the inside of the vest where hand pockets would be on the outside, so to speak.
I've only tried mine once, on a quick trip to the East coast. They have one wire leading up from each battery pack to a heating element high up and either side of the chest, roughly the size of a fag packet. I wasn't expecting much from it, but I was pleasantly suprised. At low speed you can feel the warmth build up, and at high speed the warmth goes, but the cold doesn't take it's place. I got about four hours out of the cheapo Maplins batteries and would expect longer from some decent ones.
I doubt very much they can hold a candle to the likes of Keiss, Chilli or Gerbing etc, but I have no experience of them so it's a case of never having tasted riches, I can live with being poor. What it has done is convinced me that if it lasts only one trip and gives up it hasn't cost me owt to find out, and then I may well invest in one of the proper jobbies, cos it weren't half nice having a bit of warmth inside the Rukka.
