Alpha, Beta… all of that doesn't exist, you people should stop naming these like that, because it's wrong. And what is a "Beta Disc"? If you're talking about the demo, say demo
There's no "Beta Demo" or "Beta Disc" for normal gamers, just sometimes (which is normal), it happens that there is some differences in a demo compared to the final game. There's nothing wrong with that, that's why it's a demo.
And "alpha" stands for "A" which is the first letter of the alphabet, so it would be hinting at the earliest possible development stage of a project, which we probably get to see in 0.1% of the games, so we can't talk about that
The driving is certainly not in "alpha stage", because alpha stage at this point would be the first ideas on a paper and some drawings on how the cars should handle.
Probably it will get polished, yes, but I highly doubt that it will change a lot.
BTW, was the handling in the DSF demo different? Because a friend told me that it was not like in the final game. Several people I know didn't want to buy the game because of that, that kind of explains it now.