I just got a Nuvi 360... I think you should take it with you. It's very simple to use and tracks well.
The Nuvi 250 on the other hand... issed:
There's not really much to using it. Turn it on... and after going thru the initial settings (like what your language is, what guidance voice you want, what time zone, etc.)... it'll lock on to a signal. Then just tell it where you want to go... or just leave it on to let you see what surrounding streets you are driving thru.