The only issue I've noticed is that the accuracy wanders if the device is stationary. It always claims I'm moving at 0.1-0.3MPh in a random direction and can jump 5 or 10 metres. I find it hard to believe my house is shuffling around on its foundations that much I know this is a GPS issue, but it'd be really helpful if Maemo mapper could ignore speeds less than 1MPh, for example.