My impression is that the 100gr Horn HPs are noticibly more "explosive" than the 110 Speer TNTs. I've never used 120s. The 100gr Horn will vaporize gophers and prarrie dogs. I use varget, mostly middle of recommeded load data, about 3,000 fps. The only coyote I ever shot with my 7-08 was with the 140gr Rem Fact load.
Try a box of 100gr Horn HPs, they are accurate, are designed for varmints, and will give a little less recoil than the heavier bullets.
FWIW,
Paul