The "Baghira" model encompasses the StreetMoto/BlackPanther and the Enduro. The SM/BP is a supermoto with 17-inch wheels and sportier tires, while the Enduro is a dual purpose bike with 21" front and 18" rear wheels. To complicate things further, the Street Moto is offered in both full height and reduced height versions. The "full height" model has the same suspension travel as the Enduro, whereas the "height reduced" model has the same suspension travel as the Mastiff. Both Mastiffs and Height Reduced SMs feature an unadjustable front fork, whereas the full height SM and Enduro models have compression and rebound damping adjustments. The Mastiff is a differently styled supermoto that utilizes the same frame and engine as the Baghira, but is only offered with supermoto running gear (i.e. 17 wheels, lower suspension). If I'm not mistaken, the Mastiff was available with both cast and wire spoke wheels, whereas the Baghira models were only offered with wirespoke wheels. I'm pretty sure that the cast wheel Mastiffs are fairly rare, however. The StreetMoto was usually delivered with MT60 Pirelli dual-purpose-ish tires whereas the Mastiff was usually delivered with something a little more sport oriented.
The StreetMoto and BlackPanther differ only in color, with the BlackPanther being black and the StreetMoto coming in various colors like red, yellow, and gray. The Baghira Enduro was available in black, the other solid colors, and some weird color scheme thing that may or may not have been available on the Street Moto. The Mastiff looks...different. It was available in various color schemes but the one I've seen the most of is some variation on blue body panels with either black or gray insets.
I think I'm right about all that. It's pretty much just what I've picked up from my manual, perusing forums, and ordering parts