If you have room for an extra VHF antenna, I'd recommend a standalone AIS receiver or tranceiver. Radios with AIS listening certainly work but they are very awkward to configure to not go nuts with collision alarms when sitting in a harbor full of close proximity AIS targets. If you want your MFD alone to handle the AIS notifincations/alarms where it's easy to configure, get a standalone AIS hardware and add it to the network. I think the alarm can be disabled in the gx2400 but it's not simple. For a basic radio, the standard horizons with a G suffix (built in GPS) are a good reliable known quantity but I like to keep them wired simple,