I also had a brief tour around the peak district this evening. Tried out the new heated grips, and they were toasty! Ambient temperature was 11°C and parts of me were chilly in a summer jacket but my palms were sweaty, and that was in the lowest setting.
Only thing that bugged me slightly is the green light telling you the setting. It's on the edge of my vision and as it goes in and out I keep thinking I've left the indicator on!
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