I have a 705 and use it on just about every ride. A 705 or 800 will do what you want. As the others have mentioned, you will need to buy map set as well. Downloading things from sites such as map my ride is really simple and a nice way to explore new areas by following the rides of other cyclists.

I am toying with setting up my wife with something like mytracks or sporttracks on her droid. Still need more info on battery life and to find a decent stem mount for the phone. Her Droid x has Ant+ capability, but this is not enabled in the programs yet as far as I can tell. There are some bluetooth optioins for HR though. Gotta carry the thing anyways, might as well put it to work.