"Simple to use with an open OS"4.5 starson by invictanewsletter
Pros: You can install multiple GOS programs fairly easily. I have Tom Tom, Destinator, and Mio installed and can choose whichever I want to use for a particular trip depending on the features I need (TTs, elevation, POI's, etc.)
Cons: It is a little slower than a Garmin, for instance, but it's a decent performer, certainly for $100 or so.
Summary: There are better, but if you don't mind getting into the code a little, this can be a very fun little GPS.