OK, thanks for the info, and some valid points here. A couple more questions on the nav system...
Setting aside the questions about paying for map upgrades (which I am not inclined to do, at least not often), how is the system in general? How does it compare to, say, a dedicated Garmin GPS?
Aside from paying for maps once in a while (I assume that can be as often or as infrequently as you choose - ie there's nothing that requires updating the maps on any schedule), are there any other ongoing costs/fees/subscriptions to use the nav system fully?