I would say that the Dearborn Inn is your best choice among the Detroit Area Marriotts.

While I have only attended meetings there, my co-workers were quite pleased with the level of service that they were provided. (Definitely when you compare it to the Detroit Renaissance Center Marriott)

This is a vintage facility, with quite a lot of character. If you are spending any time in the Dearborn Area, the DI has a great location. It is very close to Ford's WHQ, and across the street from Henry Ford Museum and Greenfield Village. Also in the immediate area you have a fantastic Middle Eastern restaurant (La Shish), a quality Vietnamese Restaurant (Annam), and Buddy's which is a popular local Pizza chain.

If you have any other questions about Detroit area Marriotts or the Dearborn area, just let me know. I've spent the last 3.5 years traveling there.