Even with just a combo GPS/FF, it is good to have a backup GPS to get home.
I carry a handheld for that purpose with keyport harbor and tip of Sandy hook as the only stored locations.
Single point of failure i the real down fall of any networked or combo system and is a real threat.
I see the best usage of networking (aside from DSC) is multiple monitors on boats that can accomodate them. Even still some redundancy or backup is needed.
My pops has a Standard Horizon combo GPS/FF/VHF, but just bought a backup GPS/FF just in case and already has a redundant VHF radio on boat.
Definitely don't want to be the guy cruising around raritan bay (or anywhere else) pulling up to people and asking. Where am I?
