I like my Tom Tom GO. ( the original version)

It's totally self contained. With a charged battery, there is no need to have any wires dangling across the dash. It's pretty easy to use. The built in speaker is VERY good. Loud and clear.

Is it perfect? No. I run into map issues. But I suspect that happens on any GPS navigator. Roads change. IT takes a while to get stuff into the databases. IT does "weird" routings some times. But it's really nice about it when you deviate. No nags to "get back on the route". It quietly and quickly re-calculates a new route and continues to direct you.