What is best Mercedes Benz Diagnostic Tool？

Star C4, and are software updates available.

MB SD Connect Compact 4 MB Star C4 Mercedes Benz Diagnostic Tool DOIP V2023.03 With Vediamo and DTS for Cars and Trucks
New software released by Benz Company after 04/2009 by diagnosis new cars.
where is best place to purchase a MB Star C4 system?