We have these.
Fargo
They are def. warmer but if my hands even start to get cold they freeze.
I ended up ordering the hothands(link below). They get really hot you cannot wear reg. gloves you have to wear thick ones and even then you have to turn them off every now and then. They were super easy to hook up (the only con was finding somewhere to put the excess wire) Only 50.00 And you can unhook them whenever. I love them.
Oxford Hot Hands Heated OVER-Grips Motorcycle 7/8" Bar :eBay Motors (item 270337758373 end time Oct-27-09 14:24:48 PDT)