It helps a lot to hear from experienced rodeo shooters. The best way of course to go myself and see what it is. And yes, I always can come back there another time.
I checked my camelot fest horses pics, DA 70 actually was not bad, even too close sometimes. So, I will bring Pentax only, 300mm and 70mm just in case.
However, this idea to shot rodeo pushed me to think about one very good zoom to buy. For sure I don't want 50-135mm, or 60-250mm due to unreliable motor. Maybe, Sigma 50-150mm... Anyway, it's better wait for FF first