There are three major vendors of Tow Bars and the same three are the major vendors of Base Plates. A fourth vendor, NSA, only does Tow Bars.
Tow Bar, of course, connects RV to towed vehicle. A few have unique features. NSA's Ready Brute tow bar incorporates braking. Blue Ox has a model with braking too. But basically they're more alike than different.
Base Plate provides a secure attachment for the Tow bar without compromising the integrity of today's unit body, plastic faced, vehicles. Again, same functionality, but they often differ widely in how they attach, how invasive they are, the coupling height.
Good news, is the base plates and tow bars from different manufacturers (Blue Ox, Roadmaster, Demco, NSA) can be adapted among those brands.
So I suggest: Become familiar with the Brands, Models, User Guides AND INSTALLATION INSTRUCTIONS. You may find that one Brand will meet your needs across the board. Or, you may find that you get a better setup by mixing brands.
If God's Your Co-Pilot Move Over, jd
2003 Jayco Escapade 31A on 2002 Ford E450 V10 4R100 218" WB