Maybe it's just me, but I'd prefer actual quality (like RSS, URD, VRC, Bazza, Esprit3905, Guerilla Mods, Shaun Clarke, AccAkut, Siim Annuk, A3DR, MSF, Patrik Marek, GeroDa74 etc) over having 300gb of total crap like this. What do you even do with it? The performance bears nearly zero resemblance to the real cars, so you can't even include these contraptions in a realistic AI car lineup.
And as far as actually driving these pieces of junk, tire heating in particular is nearly always totally screwed up, which means you can't really drive these "cars", nor can they be put to use as AI opponents. Very occasionally, RTM will include just enough stolen-from-Kunos suspension and aero to result in a decent-driving car, but I've yet to see any of them which had the performance characteristics of the actual car being "simulated". So, we're back to them being pretty worthless in a hardcore sim.
So, what's the point of collecting this stuff? Are you just driving half a lap and moving on to the next acquisition-for-its-own-sake? I have every available RTM mod and not one of them drives as well as the same car in Forza 7.
I can't think of anything more damning than that.