Even with a GPS, I believe you still need to have a general idea of where you're going. The GPS doesn't always pick the best or most direct route. Most of the time I'll look at a map, and if I decide not to follow the GPS route, it will recalculate to keep up with me.
TomTom has free lifetime updates, but I don't see that as a deal breaker. After all, how many new roads are being built these days? And in a few years the technology will probably evolve enough that you'll be upgrading the unit anyway.
