PRO-95 vs PRO-97
There are a few threads here on RR that "compare" these two models. Some people, including me, actually like the PRO-95 better. I'd compare it to a software "upgrade" of your favorite program; often people like the "old" version better.
But to answer your question; I feel the biggest "update" is the addition of CT/DC decoding on the '97. Then there is Signal Stalker II and inclusion of LTR trunking capability.
On the other side; they screwed up the volume & squelch controls by putting them into one dual pot (that apparently has a history of failing). While the display is now 16 characters per line, the bank TEXT tag does not display when the scanner has stopped on a conversation. Most, if not all, of the software bugs were carried from the '95 to the '97.