After a VERY long layoff I am getting back into biking. When I was riding before, GPS stuff (at the consumer level) didn't exist. One capability that I would like is to just 'take off' from somewhere and ride for an hour (or whatever) and use the GPS thingey to get me back.

I occasionally use a auto-based TomTom, but from the reading I have done it would seem that the capabilities of these much smaller bike based devices are much more limited. Is it reasonable to think that this can work? Are there devices to avoid if this is one function that I need?

Thanks.

dave