Well for starters I don't get the separation between "Bike Navigator" and "Smart GPS Bike Computer", when most from the latter category can do navigation too
I tried comparing the Binavi Air to a few of the other models and I get two columns with basically the same checkmarks. Main differences seem to be on the size, but then I don't get the need for a Binavi and the IGS800.
Probably if I study more I might get it, but to me it's not clear at all at a first glance.
And note that I'm not hating on the brand, I own the BSC300 and would be curious to upgrade to something with a Climbpro feature