You will love the 4212 - it's a great unit. I had a smaller 500 series Garmin on my last boat. Although I liked it, I'm over 50 and couldn't read it without glasses. The display in the 4212 is terrific. I also have it tied into my engines so I get real time fuel economy, fuel level, engine information (actual temp and oil pressure), etc. I have XM weather which I really love and also have an 18" HD radar unit. I think that Garmin has the best user interface of all the manufacturers and have had great customer service (with questions or issues).
You did a great job on the installation.
Enjoy!