It's been through 2 updates since we last used it here - and one since SRO ran their season last year so that might be fixed.
I haven't really driven it since then though so can't comment.
I have loads of top quality mods but will need a lot of time to make a usable list!
So I'll start the easy way as I have only a handful of paid stuff.
I've yet to see RSS or VRC make anything rubbish that's not worth the price (Provided it interests you at least)
RSS:
https://racesimstudio.com/ (I massively recommend the old GT1 and GT-n packs plus the older F1 cars, the rest is all to modern for me so can't comment).
VRC:
https://vrc-modding-team.net/ I have the Chevrette (Worth it for the sound alone) and the 2 TA2 cars which appear pretty bang on for their real counterparts.
The TA2's and RSS GT1/GT-n's are so good I wouldn't hesitate to run series with either I was sure enough of people actually turning up and buying them (Lets face it - plenty of places (here included) have run seasons in far shoddier cars)
Near enough all track by Sergio Loro are of very high quality if he's charging for them. Rouen and Sandevort are truely standout circuits and beat the hell out of any free versions, I'm hoping he'll do the GPLEA version of Clermont so that track can finally be done justice to aswell....
Sergio Loro's stuff:
https://f3classictracks.sellfy.store/