and think it is a real bargain. I use it with a laptop charting program, though, so the small screen is not an issue. I also have 7" Raymarine radar/chartplotter outside. The CP180 is actually the master, drives the boat, but is not waterproof. The laptop does the planning, routing, etc. and uploads the result to the CP180. The CP180 uploads the routes and waypoints to the Raymarine, and also provides the GPS data for all the devices. And provides information to the autopilot. It also displays AIS so I don't need the laptop up. How do you navigate now and how do you plan to use the CP180 or CP300? If you just want to know where you are and how to get around a bit, the CP180 has a crisp display, good zoom and other features/controls and should work fine. Add a few of your favorite waypoints and you are all set.