What brand of marine instruments

[lifeofreilly57]

I agree on avoiding wireless, I come from the industrial controls side of things, the commercial controls suppliers were pushing wireless devices years ago but have backed off a bit. To that end, yes it's less wiring but it doesn't take much rdf interference to ruin your day.
Most now use NMEA 2000, which is really a more specific use of DIVICENET, an older form of industrial control communications protocol, it is also used in automobiles. The only drawback is that equipment drops to devices should be limited to 15' or less. When i installed the comm backbone on my boat, which is 47' long, i had to think it through to make all the drops fall witihin that range. WIth NME 2000 you should technically be able to communicate with other makers devices, with the proper set up of course. It's an older comms protocol but pretty stable, which is why it was used in industrial settings originally but has been slowly phased out in favor of ethernet in those applications, now in industrial applications ethernet is being replaced by fiber optics due to the amount of information being passed, but that shouldn't be a problem with these small boat systems since they don't need the capacity or speed to that level.
Another consideration is that most systems that use NMEA 2000 also power the chartplotters and device through that backbone, in my case I had to have two power drops to the backbone due to the length of the backbone run and number of devices. I also had to run an ethernet connection between the two chart plotters to enable the radar to be seen and controlled from either screen, or both simultaneously.
The AIS is from another maker but should talk to the main system to display the information, I'll know in about a week, I'm finishing up the battery and charging system set up wiring and will power up when thats all set.
Some things to consider when looking for a new system.
Technically this system should run faster and consume less power than the old system, we'll see, the new 4G radar should use significantly less than my old unit. Now for the next learning curve, setting the whole thing up and getting everything to play nice in the sandbox.
As for companies backing they're systems, I've had experience with most of the major makers, they all have their good and bad points, it just comes down to which is easier to live with.
I ought to know, I used to be manager of international service support for a manufacturing equipment OEM, I left when the new management thought it was a frivolous expense to support customers to the level I thought appropriate, that and other changes in their philosophy caused a 40% drop in sales in the 4 years since those decisions were put in place. Funny how that works, maybe some of these companies should take notice.

[lifeofreilly57]

One more detail, if your looking to eventually add another screen and use a 4G radar you may need to be able to run ethernet between the screens, on some of the smaller units they only have an ethernet in port, which would require you to purchase an ethernet router to add another screen to the system. SOme of the larger screen already have both ethernet ports so you don't need the router. Make sure to check this out when you eventually purchase your system. It depends on the maker and models in their line.