As an "early adopter" and self-admitted gadget freak, I have a nearly unconscious tendency to lean to the new, the shiny, the integrated. The "glass cockpit" draws me.
But then my engineering side steps in and says, "All your eggs in one basket? Really? What if it fails?"
That is a very valid question.
There are tremendous advantages to be had with integrated instrumentation, and not just in conserving display real estate. Being able to overlay radar and depthsounder information on the chartplotter display provides very real advantages over the same information viewed separately. But if that is your only way to see, for example your speed, and it goes dark, then what?
And does anyone really believe that the modern all-electronic systems are more reliable than the older electro-mechanical ones? The best that one could say is that the new systems have different failure modes, but I personally think that is being overly generous. In designing systems for reliability, simplicity is a virtue, and modular design partitions problems.
Problems that occur with an older electro-mechanical instrument can frequently be fixed on board by the owner, rather than by calling a technician who will charge an arm and a leg to swap out expensive circuit boards until things are working again. Most (but not all) problems with older systems will be due to corroded connections, which are an easy fix. And did you know that even the most modern and sophisticated airliners out there (787 anyone?) are still required to have a plain old magnetic compass, a conventional mechanical altimeter and a turn-and-bank indicator (a steel ball in a curved glass tube full of liquid) on board in the cockpit? (Scott will probably correct me on this.) Just in case.
Finally, there is an intangible. I have seen boats with such a large computer display above the compass and directly in the view that commanding the helm surely has become some kind of real-life video game. One of the joys of sailing is the totality of the experience... of capturing the wind for propulsion, of the boat parting the water and moving thru it, of the sights and sounds and smells of the sea. When you were a kid, didn't your mother tell you, "Get away from that TV and go outside!" - sure she did. And she didn't mean for you to take the TV outside with you. Like having a generator and a TV at a campsite out in the woods, sailing as a video game misses part of the point. Perhaps the major part.
I am not saying that we should eschew the advantages of modern technology. But keep it in perspective. Hang on to your single-purpose instrumentation, and "Get away from that TV and go outside!"