I've not had Sat Nav before now, so I suppose you could say I've nothing to compare the TomTom One V2 to, but I have had plenty of gadgets in my time both good and bad, so I do feel qualified to give my views on this product.
The software is superb, so easy and intuitive you don't even need to bother reading the instructions, which if you do, are well presented and meaningful.
The signal lock is brilliant, I'm able to use it quite happily in the house, and whilst driving it's not lost the signal once.
The windscreen holder is simple in design but works extremely well.
Battery life seems good, the supplied USB cable is a useful way of topping this up whilst backing things up on your PC, or adding new points of interest to the device.
Very easy to add additional points of interest, such as the location of speed cameras and fast food outlets, petrol stations etc..
If you deviate from the suggested route, re-calculation is automatic and takes around 5 seconds from my experience.
The unit seems well made and fits neatly into the palm of your hand, it would fit very easily into a suit or coat pocket, making it ideal for use on foot as well in the car.
If your mobile is GPRS enabled, I believe it's even possible to pair the One with your mobile via Bluetooth thus making it traffic aware to avoid problems on your calculated route.
The price is unbelievable considering the usability, build quality, and expansion options of the product.
I highly recommend this product and rank it in my top 3 gadgets I've ever purchased, alongside my Roku Wireless Music Player and the Sky+ box.