Honestly, i don't consider forza and dc to even be in the same camp. I think the real battle there will be Horizon 3 and driveclub 2. Although DC benefits from closed circuits as opposed to fh's open world, I'm excited by the prospect of what greater familiarity with the respective hardware will bring.
In all fairness, while DC is currently the eye candy darling, a lot more credit has to go to F5 for the consistency of their presentation. It doesn't flinch from 60 Fps and it shows. It's not in your face arcadey like DC, but IMO I get a better sense of speed and the FFB provides a nicer sense of weight. To say nothing of how much Forza's sound design really supplements the visuals. I think Forza 6 will look incredible.
To that end, I finally got my T300RS yesterday and gave DC a whirl with the wheel. definitely a different world compared to the more simmy racers, but my first race during a thunderstorm was exactly as terrifying as i'd hoped