The AVN2210p is far from perfect, but it's a nice example of what can be achieved by combining personal navigation and in-car entertainment. It's a very solid unit with a couple of nifty features and the fact that the GPS unit is detachable will be a selling point for many consumers – not to mention its very reasonable asking price.

If you spend a lot of time driving around unfamiliar areas by yourself, the iQue M5 could be a substantial time saver. It is well-built and easy-to-use, but a little pricey.

The zumo 550 is without doubt an excellent option if you need a GPS unit for your motorcycle or scooter.

A large 3.8' screen and fast processor speed can't compensate for the bulky size and lack of both a touch screen and internal battery on the iCN 635. The hefty price tag also counts against this unit.

The TomTom GO 500 adds handsfree capabilities to an already impressive set of GP features.

While Tom Tom does get credit for trying with the Rider, there are some key flaws with this GPS solution that have to be overcome.