Assuming KA takes the maximum time (3hrs) to spawn...you coulda killed Ovni 4-6 a hr (assuming 10-15min respawn. I've personally killed ovni 4x in a hr, but not quite sure if 10 or 15 min repop. That's 12-18 chances of a 13.7% drop (bullwhip), vs a 8% drop (Velocious)...
Also, in a KI farming pt with 4 people...after 2hrs 2/4 should have a full lacovie set. Only 2ki needed and it seems to be the most common set to drop.