| 3/6/2017 12:33 PM Good little unit for a good price by Colin Easy enough to set up. I measured my own 700c x 23 wheel circumference which took a few mm off the value in the guide chart (too bad, 'cause I'd be getting higher speed readouts otherwise ;-). I also found the battery in the sensor unit failed the charge test (there's a button to push), so I replaced it at the start. The unit works well, coming on with a push of a button or dautomatically as you get rolling. The calculated speed and distance seem credible from my previous experiences. The calorie counter can only be for the feel-good value as the unit has no data on your wheight or the terrain you're travelling - a sales gimmick I can live without.Wireless function: I've never had any interference from my lights or anything else (a dubious explanation I've seen, for why some units don't work well).I recommend this unit to anyone who doesn't need a gps on their handlebars, but just wants to know their speed, distance, average, ride time and actual time, odometer - forget the calories!