Larry asks:
"If you were given a choice between 2 integrated systems that were completely separate from each other or 2 non integrated systems with 6 screens (2 each for radar, sonar, gps) which would you prefer?"
Of course, 2 integrated systems with 2 screens are better than a system with 6 screens -- but that's not my point. I have not suggested two integrated systems.
My point is many boats are currently with all mounted electronics in one screen -- those with a radar, a chartplotter, and a sounder have three mounted screens, each of which can be used for navigating if anything happens to the others.
Dusty said: "I don't think an integrated system is any more dangerous than individual units if backed up. My compass is remote, and gyro controlled, to avoid all the manetic junk in the dash area. A little GPS handheld is certainly a good backup, and I use one often as a primary tool just to keep in practice. Paper charts should be aboard, though, and if boating in unfamiliar waters they should be required safety material."
Again, to clarify, my point is that a single MOUNTED integrated system that replaces three separate MOUNTED systems is more vulnerable to failure. Those MOUNTED systems are the best backup in foul conditions.
I heartily agree that charts, handhelds, & compass are all backups, and we carry all -- but that in foul conditions -- like night, in a fog, in a storm (and of course, none of want to be out in those conditions, but all of us with any experience boating have been caught by unexpected circumtances) -- a MOUNTED system is far superior to handhelds or paper charts. It has also been our experience that many folks, new to boating, have little or no experience with charts, bearings, and small screen handhelds under tough conditions.