Up-to-date maps aren't usually free. The ones that are, if you can even find them in these days of sub-$100 GPS units, are loaded with advertisements. Also, paper maps have limited range, don't store points-of-interest, don't lend themselves to recalculating a route if you miss a turn, and can't be handled while driving.I read a map. It's free.
I like them and prefer them for getting an "overall view" of a trip in planning, but with my Garmin I can get the same thing on my computer. Or, with MapQuest. I now own a pile of beautifully-printed DeLorme Gazetteer map books, all hopelessly out-of-date.
No paper maps have been able to do for me what the Garmin has. It's not perfect, but they get better and better all the time. The Nuvi 1490T I bought for $149 (Radio Shack sale) for my wife just blows away my 4-year old Zumo 550. Now I ponied-up $89 to upgrade each for "lifetime map upgrades", I never have to worry about using obsolete information.
Works for me. What doesn't work for me is OnStar. The only thing I wish I could buy is the remote lock/unlock and perhaps the ability to kill the car if it were to get stolen. I do not want my car capable of turning me in for speeding though.