The LCD displays (nevermind the CRTs) in the 15 year old PC12 I was flying, and the 10+ year old TBMs are holding up fine. The tech behind those displays has done nothing but improved since they were manufactured. I'm going to spitball a guess that the cost of maintenance on those DUs and their associated boxes will be on par with replacing all the steam gauge equivalents in a similar setup. That's not just the sixpack, but will cover any navigation and engine instruments, as well as any annunciations. I think the difference between the two will be a wash.
I agree. The aging instruments in our planes are only going to get more expensive to replace/repair if keeping original. I think the time the industry has had glass, we have pretty much shown that these things are just as if not much more reliable than the old stuff. Think NO GYROS.... (this must make new aircraft without "black boxes" quite hard for the NTSB folk to determine if there had been an instrument readout failiure). I'm hoping that the MFD will be able to be the redundant counterpart to the PFD like G1000 does...
