While I have no doubts that we would have reached our destination just fine without the navigator, the Garmin helped tremendously in ways I had not anticipated. Whether we needed to find a Papa John's pizzeria in Billings, Montana, a motel to stay for the night in Kadoka, South Dakota, or the route to tourist attractions off the highway (Corn Palace, Mitchell, SD), the Garmin was there. Riding on those long stretches of highway with little in sight, you often wonder when you will have another chance to stop at a rest area or gas station. Even though it wasn't always 100% accurate, the unit was able to give us some inkling of what was to come.
Seattle driving is a bit of a mess. Downtown always has heavy traffic, streets intersect in the middle of steep hills, parking is expensive ($1.75 an hour at the meter -- if you can find a spot). There are many one-way streets and thick highways criss-crossing one another. It gives us directions to the entrance of the Arboretum, to the co-op, to the movie theater and, when we can't find it ourselves, to home.
Like I said, it's not perfect. It doesn't have every single destination in its pre-programmed list. Sometimes the route is not direct (three left-hand turns?!), but all in all, it is incredibly useful. The size allows it to be stashed in a pocket in case I'm shopping downtown and want to find a specific store. I look forward to taking it on all my forthcoming trips as I get more familiar with the city -- even if it means sacrificing the better (read, more engaging) way of doing things.
(Plus, it's just one new gadget to accessorize. Last week I ordered this little, leather protective cover in brown.)