I got one last month, it is pretty crap! my phone did a better job.

Only got one because it was pretty data usage heavy on my mobile and drained the battery a lot.

But found where my phone would give me a few options on which route to choose, the sat nav doesn't, it's either the fastest or shortest.

One example is I live near Kingston and to get to Harlene's Aunt in Croydon my phone would take me on the Kingston bypass so I didn't get stuck in the town centre traffic. However no matter what I try within the sat nav settings, it always takes me through Kingston town centre!

It only cost £50, so I guess you get what you pay for!