"Alpha-bid does not offer tech support for this product."

That is a red flag to me. It looks to come with a connector for the MB diagnostic port as well as the OBD-II port, but it gives no clue as to its functionality.

You can get all of the engine codes (perhaps transmission codes, if applicable) from the OBD-II port, but nothing else. The MB scanner is something like $9K for the first year including license, and $3K/year for the license fees for subsequent years.

Phil has a product for a grand, but I haven't yet called the manufacturer to find its exact specifications.