Vaal Rhebok is the hardest plains game to get in RSA. They are restricted in their range, they have very good eyesight and hearing, they move very fast and they live in rough and rocky terrain.
This one was about 7 inches in horn length. He busted one off rolling down a hill but we found the piece and the taxidermist repaired it. They only weigh about 40 lbs and this one required a shot of nearly 300 yards in a strong wind. He is the only life size mount I have.