I can tell you that the community aspect is rather weak, SMS have had a clear dev process and direction from the start and the community have had much weaker impact than I hoped for. I have to hand it to them though, it's a good business idea on there part and a good way to build revenue through the dev process. But in all honesty I feel far more like a paying beta tester/investor than a valued member of a community that can make a difference, because they knew the path they were taking all along.
I just wish they had abandoned the flawed Madness engine and built a new physics engine from scratch, or used another proven physics engine. Despite improvements with the tyre model and FFB the core physics still are Shift like and the car behaviour has the same issues; lack of front end grip, sluggish chassis response, somewhat floaty and light, inaccurate steering response and slippery sluggish tyres that lack bite on turn in and progression under throttle. The suspension movements are also unconvincing.
Where it perhaps lacks the most is that the car/tyres don't feel pinned to the road/track by the weight of the car, it doesn't feel planted like a real car or like the better sims do.