I havent shot the HAPs, but from my understanding they lack the internal skiving that promotes expansion on the XTPS. Ive also only shot XTPs at velocities far in excess of what they are supposed to be used for. Expansion there tends to be pretty dramatic.No game with any hap, but various media, and the drama was lacking in the trauma. I believe we should be able to have the best of both worlds lol. Competition bullets often serve multiple purposes well, but the bullets I use for prairie dogs are not often the ones I use for larger game, perhaps the .45's larger meplat would aid in wounding, but from my experience, they are not my best of both worlds bullet.
The note able exception are the .454 240xtp mags from my muzzle loader. Those were right in the expected velocity range, and showed little to no expansion on our goats, and one axis deer....even going end to end thru a goat, and breaking both shoulders on a small spike....That may simply be the way those bullets work, or they may need a harder target to open up.