My boat came with a full Nexus suite of instruments including multicontrols, wind instrument, multicenter (chart plotter), fluxgate compass and autopilot. They were about 10 years old when I got the boat and had spent all this time in California and Mexico. The log transducer was no longer working and the wind transducer gave up the ghost a few months later. I bought a server upgrade kit which included a new FX Server, new multicontol instrument and a combined depth and log transducer. I also sent the wind instrument to a guy in Florida for repair (at the time ComNav had given up supporting Nexus but I think that has changed).
Overall I'm happy with the set-up. I've connected the server to my laptop running the Nexus racing software an that gives lots of control over the server. The system has been reliable although it is sensitive to the quality of the connections. The down side is support is limited. Very few cruisers use Nexus and there are a limited number of places to get service. I have a long standing issue logged with Comnav where whenever I connect my wind instrument, the log stops working. It's been unplugged for a couple of years and at some point I'll pick up the problem and try and get it resolved.
I'm currently reconfiguring the electronics, connecting my HDS Chartplotter, Icom AIS and Standard Horizon VHF into the mix.