For example if I skip a step to take an exit(because I find it faster by using the next one), it'll spend the rest of the way trying to reroute me to go back to the step that I skipped. So I can be pulling into my driveway, and the system will be trying to send me back 50 miles to take that exit that it wanted me to take.
Granted I have the cheap $150 system, since I barely use it, so maybe the more expensive systems are smarter
There are very few features to differentiate GPS systems. The chipsets themselves have become pretty good, and the good ones aren't terribly expensive. Instead vendors have to find other ways to do it. Inevitably that's going to be finding really irritating ways to make people want a higher-up model.
On another note, I really should get her a new maps DVD..
Until it got stolen.