I don't use either, but I'll echo that you should be fine with the rifles you have already. I don't use Sierra GKs in my hunting loads any longer, the 165gr .308s (in .308, .30-06, and .300 Wby) and 300gr .375s have lost their jackets every time. Never used the TSX. Hornadys and Noslers have always worked for me.
Practice, practice, practice ... and conditioning, conditioning, conditioning