I have the 305 and just use the Garmin software and the free MotionBase when I want to send a link to someone on a recent ride. I believe I read a post in the MotionBased forum or might have been BF Forum, about someone that found a way to charge the unit on a un-supported tour. You could always just pack the plug and just find a plug and give it a quick shot of juice at a rest stop.
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Brian | 2023 Trek Domane SLR 7 AXS | 2023 Trek CheckPoint SL 7 AXS | 2016 Trek Emonda ALR | 2022 Trek FX Sport 5
you should learn to embrace change, and mock it's failings every step of the way.