Any company better than the other? Not trying to step on sponsors toes or anything or are they pretty much the same?
Oil Analyzers if you are quite familiar with the results and can interpret the report yourself, and if you don't need accurate wear rate averages for your engine/transmission, or you need accurate Fuel Dilution.
BlackStone if you like a more detailed interpretation of the results and need accurate wear rate averages. They share the raw data for your engine if you ask.
I use both.