I have one, and would highly suggest you get a RoadID as well. Just read one of the numerous stories they have on their site. If you run or bike outside, you have probably had many close encounters with cars/trucks just like myself. For your peace of mind and yours familes:
They are also to become one of the first affiliates of a new site as well.
By clicking through my link you can also apply coupon code: ThanksAaron351142 for $1 off.