I currently have gold in the first 2 events but only bronze at suzuka (some 4 seconds off gold), it is very difficult but very doable to achieve. I managed lvl30 Bspec which unlocked the sebastian vettel challenges, suzuka is extremely difficult to match the time, the other 2 are very doable though to even get gold. You gain a massive ammount of experience for completing the challenges, i went from 27-32 and it will likely take me to 33-34 if i manage to gold suzuka at some point.
The car isnt really very enjoyable, even on 1 FFB the forces are very very strong (shakey and alots of rumble, you need to grip the wheel tight) and the car can be annoying and even tiresome to drive, it is extremely fast but as a result extremely sensitive. Personally i don't really like the car, and have not really driven it much. Averaging 300mph at indianapolis gets boring after about 2laps.
There are a few different ways to get the car, i have the X-1 Vettel with the red bull F1 car colour scheme.