Just saw on their web page about the release of the mini..... $99 and comes with the speed sensor. Looks like a cool little unit but needs your phone on and paired if you want GPS as it doesn't have that built in.
It will store ride data that can be uploaded via your phone. Battery isn't rechargeable and uses a CR2450. They say it can last 12 months.
It would be a step up from my little Sigma....