I actually went to this event last month in torrance. When you arrive, they give you a brief lecture about the new F30, then they let you drive the cars by yourself!
You can choose to drive one of those competitors then drive the 328 or 335, or the other way around. This is a bmw corporate event and there is no salesperson seating next to you while you're test driving.
When i went, they were just being nice and let me drive all of the cars they had. I drove the IS250, C250, A4, 328, and the 335. After the test drive, they even gave me a bmw hat and a $1000 credit towards the next purchase/lease of my BMW
Definitely take advantage of this program and register yourself now!