Corcoran is well known. Have you talked with some of the agents?
I think you too should talk with Keller Williams. You may not believe this now, but there is a lot of money riding on your decision.
Here's to hoping you land at the right place for you!
Also, what tools are they offering you as an agent (i.e., ongoing training, floor time, advertising, lead generation system, etc.)
I am sure you will got many more good advice from this post.
Good luck and welcome to the world of Real Estate!