I have to disagree with a few other statements I am reading here. I am sure
I will catch it, but the world is changing. Mike makes some good points.
Cessna and Beech will be happy to tell you about demand for the new panels.
It has actually sparked the heresy of proposing new designs within Cessna
(Unless they are keeping the worlds best secret, don't hold your breath).

Buying a 10 to 20 year old aircraft is a way to preserve equity, but not the
best investment for everyone. The cost of maintaining them is much higher,
potentially making it cost even more to own over the long haul than a later
model or new plane. If you count the time to learn about used planes, and
your time managing all the repairs (potentially with technicians from
several companies), it can add up fast.

If you want to go glass, you could likely justify a new glass trainer, and
expect to sell it for about a 40 to 60k loss in 3 years. If you trade it
back to the people that sold it, for one of their bigger models, they
usually cut you a better deal. Otherwise, you have to sell it yourself, or
lose even more.