I would think the main reason is, if the rifle shoots it well, the 150 TTSX (Etip, whatever) is definitely going to recoil less. And since it will penetrate well, no use in getting beat up. Same reason I loaded the 120X in a 7mm Rem Mag for my Pastor in Texas. Deer and exotics were his normal game. I sent him some Federal 160 NP Premium ammo for his bear hunt in Alberta. But I was with him when he shot a big Spanish Goat/Ibex mix right at 400yds with that 120X. One and done. He is gone now, I sure do miss him.
