H2Andy:well, can we agree that an SPG is much less likely to fail than a hoseless computer/pressure gauge?
i believe that's the issue
you can often see an spg failure coming well in advance too, like in your case or Mike's case.
I just got back from Egypt where I made 20-odd dives with an spg that was cracked and flooded (darned baggage handlers...). It was still working but of course you could bet your testicals that it was only a matter of time before it rusted though and blew up. To replace it would have meant riding teh bus for 4 hours to the nearest diveshop so I just hoped for the best.... It managed to survive the trip and now it's gone to spg heaven.
R..