It would sure be helpful IF Lionel would have information as to what different "generations" of their product have in the way of upgrades and changes as they do product releases.
Example: the most recent (Lion Chief Plus 2.0) compared to earlier versions. The LC+ locomotives of recent (2017+??) manufacture are very different than the originals, and (we don't know, but...) and than the Lion Chief 2.0 versions.
The Lion Chief RS-3 Diesels - 2014 vs. 2018, LC+ 2.0 are unknown
1. The RS=3s appear to now have metal geared trucks.
2. The new metal geared trucks seem to be of a different (lower) gear ratio and older ones run away from them.
3. The boards are very different in terms of the plug arrangement.
4. Plus the stated differences in Lionel's information, like Bluetooth-capability, and improved sound.
All this vs. (now) LC+ 2.0
From what I see- it appears that Lionel will be moving toward fully-compatible (Universal Remote, BT, TMCC and Legacy.) LionChief Locomotives - now being called LionChief Plus 2.0.