I really would recomend a Deluo setup. I have the GPS unit from them and the new Routis 2k4. It is very good for that usage. It also speaks to you. It has a decent POI but double-time makes up for it in the nav functionality that it may be lacking.
Call 1-800-MY-DELUO and ask for Paul from sales. Paul will answer any questions you have and is very willing to work with you on how the setup works. He spent a lot of time with me without rushing me or anything.
Call him and tell him Mike H. with the Red-Rx7 sent you. Let me know how it goes!