Main setup - v.137
Driving Cab - v.142 IIRC, but I also have a separate folder with a newer version and offroad challenge as the only rom.
The way I have things set up, they both show up in the same list.
Current build - v.146 adds the PGM games.
I also keep a set of v.80 roms for installation on old computers.
I chose that version for a specific game, but can't even remember what it was now.
IIRC, a lot of people stick with v.106 because the video was overhauled and made more demanding for v.107.
I usually keep the current version on my laptop so I can see if recently added things make it worth updating the cabs. Haven't updated that since v.146 though.
The last big thing worth updating for IMO was the PGM games added in v.146.
There really isn't any reason to do every single update on a cab.
Don't fix what isn't broke until there is enough benefit to justify the work involved.