Originally Posted by SVAuspicious
Splitters are fundamentally bad. The best thing you can do is have independent VHF antennas for VHF and AIS.
Not sure if you noticed that the built-in splitter is circuit-protected, which I presume to mean that it blocks the VHF radio's 25W transmissions so it won't fry the electronics. I know this does not address all the issues with splitters, but it would seem to be a significant improvement vs. someone who unknowingly puts a passive splitter in place without realizing the damage that it can do when he presses the button on his mic.
As someone else pointed out, compromises sometimes have to be made on small boats. One of the reasons I decided to go with the GX2150 is because it did not require a splitter and all the potential problems that go along with it. But for others who don't want to replace their VHF, this add-on looks to be a nice design, and allows you to use the masthead antenna instead of placing a second antenna in a less favorable position.
EDIT: I'm sounding too much like a know-it-all here. I'd be happy to hear more specifics on the problems caused by using splitters. I have a lot to learn about these things, especially if you have personal experience with them.