It's installed on the boat I'm in the process of purchasing. I don't see much of them even in the used market. I assume maps etc. can be upgraded but is the unit up to snuff for S. Fla., river, intracoastal, poker run, and offshore excursions? Potential Bahamas trips within a couple of years. Thanks for any insight!

I have a 420s and love it! I think the 440s is basically the same thing with a couple more features. All you need to do is purchase the maps for the region you boat in and you're all set. I've had mine about 8 years. We just bought a bigger boat this summer and I was looking at buying a new one and leaving the 420s on the old boat but decided otherwise. No sense in spending more money when I already know and trust this one.