Waze on iPhone in parallel with TomTom shows that Waze is better. Better traffic detection, better police location, better maps. The really neat thing about Waze maps is that unless you have driven on it, it is pretty hard to put it on the map. Waze is the only sat nav to correctly identify a dead end near us - because no one can drive it. Not sure why Waze would drive you nuts - the only quibble I have is that the voice commands are a bit quiet in comparison to the music that is streaming from the same device.
The costs are a bit more evenly balanced:
- iPhone4 16 GB on eBay - £233. Waze - free. I'm assuming you have a mobile contract already.
- second hand TomTom - 60. Map updates - 40 per annum. Traffic updates - 40 per annum.
So after two years, the iPhone is winning. It is also a better concept. No more worrying that some scrote has broken into your car to steal the TomTom. No more ferreting around when you get in to set the destination - you've already done that while walking to the car. Copying postcodes straight from an email to the device. Last mile navigation - the Waze map will get you the last 500 yards from the car park etc etc.
Everyone I know with an in car system binned it for a TomTom, and the same people are now going smartphone.