Maybe it has just been a while since I have been on the BUSSE web site, but didn't they used to list their grind as a "convex". I notice that now they just list it as a "flat saber". I could be wrong, please correct me if I am.
Depends on the model. The Nuclear Meltdown line uses a 0 edge convex (how they used to list it) then other models have been been convexed edged too. Most of the newer models are saber ground with a V edge to it (unless it's the light brigade with the hollow grind), that seems to be most of the combat grade knives. Satin finish saber grounds sometimes still use convex edges.
So...comes down to model and I think who sharpens the knife too. In my experience though it's not super hard to convex INFI if it started life off with a V grind (unless the knife is super thick with bunch of meat behind the edge)
^^^^^^^^^^^ THIS ^^^^^^^^^^^^^^^^
Depends on all that. I've handled hundreds, if not thousands, of Busses over the years and have seen a bunch of different grinds. Sometimes on the same model. Even had one come thru that wasn't sharpened AT ALL !!
But what do I know as I'm sure others may be by with a more detailed explanation.