Motorola - Motonav tn20 3.5" Navigation System Review

I recently purchased the Motorola Motonav Tn20 GPS Naviagtion System from Target online for $79 plus free shipping so it was a great bargin. It has text to speech so it alerts you of street names and adjusts for night time driving. The unit includes a car charger but there is no wall charge included. There is an SD card slot for updated maps which I haven't found any documentation about how to use yet but I intend to continue searching for. My last GPS was a Pharas brand that never updated the maps so it became outdated after a couple years. I'm hoping that I can downing new maps to an SD card and use them on the Motorola unit. Also, this is Motorola's first GPS so I wonder if there will be any map undates coming our from Motorola or not or if they will even stay in the GPS industry. The Tn20 has a touchscreen that responds well but there is no stylus included. The screen is a bit smaller than my previous GPS but its really not a problem. Overall, the Motonav TN20 is a good buy for the money I paid.