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right now I have the 90watt First Gear jacket liner, I did have a Gerbings, but after 100,000 winter miles it was getting tattered, I'm still using Gerbings Gloves, they use the same coaxial plug as FirstGear.
I vote for the higher wattage just so you have it available, not that you have to run it on max all the time.
I considered the Kathmandu but went with the Kilmanjaro for the Hi-Vis
I'm working on putting together an outfit that will keep me warm without electricity, If I can do that, I can spend more watts on auxiliary lighting