I can answer this. Using a thrustmaster tx. There is some dead zone, but better dampening when playing at 900 degrees, but the dead zone is no where near the extent of forza 5. I in fact hated forza 5 with the wheel, and I've played every one. Forza 4 being the best imo. I've already gone through the demo once, and so far, it's.. Ok. Better than 5 in the physics department for sure. But, I'm not blown away. I still need to tweak settings a bit. So that may determine how I feel playing the game more. I'm more of a sim racer, so the first thing I did when I had a chance was to turn everything off.. Except for the braking racing line, to learn the tracks. I also changed the from the default 540 degrees to 900. Also.. Simulation steering, while playable, is still somewhat of a joke to me. Entirely way too much snap oversteer just like all of the other sim steering modes in previous forza's.
I generally turn down force feedback to emulate a real car. Most racing games tend to overcompensate with the FF at max, and are too heavy. Anyway, I experimented with 540 and 720, at about 70 FF (I generally use 40-50 FFin most racing game to get an even feel). It didn't feel too bad , and had much less dead zone.. I.e. Not as loose.. And then extreamly heavy the farther you turn the wheel. If I buy this game, I may end up using somewhere between 540 and 720 depending on the car. If I'm honest though, I still think that forza horizon 2 still feels better.
At least they have controller settings menu as an option time, so you don't have to continually quit out of the game to the main menu just to fine tune wheel settings.
At the moment, I'm having a better racing experience with project cars on PS4 personally (using t300rs). And I also wish the demo wasn't only carreer, and would give me the option to simply test a carline the ford GT on a few tracks.. With no aids.