So, whoever decided that running with a plastic sensor in your shoe is a good idea was not a serious runner.
I bought the Nike Sportband about a month ago. Bad idea. The sensor goes in your shoe (unless you want to cut a hole in the sole of your shoes or buy another sole built specifically for the sensor) and you have to fiddle with finding the best place for it. I surrendered to placing it above my toes inside the shoe, which probably hurt its accuracy. It was ridiculous. To keep from losing it, I’d keep it within a single pair of shoes, but sometimes I’d grab a different pair and forget to switch the sensor over. Essentially, the Sportband became a fancy watch.
Go sensorless, not senseless.