Irold I used to load my cast SWC's in 44 mag and 45C hot for deer hunting - 1300 - 1400 fps. They worked well, but with the recoil and muzzle blast that goes with it. My usual bumming around in the woods load is the same bullets and calibers, only loaded to about 1000 fps. After taking several deer with my "bumming" load, I have noticed little difference in killing power. usually complete penetration, and a dead deer. If you plan on longer range shots, using a scope, where you can take advantage of the slightly flatter trajectory, and want maximum down range energy, then you might want the extra velocity. But for closer ranges, you should find the 1000 - 1100 fps load effective.
Have used the XTP a lot in the past, and have a lot of confidence in it for deer sized game. But, it is not a bullet you want to load down, and expect good expansion. Loaded down, it often acts like a solid, with no expansion, and a poor cutting profile, as compared to a SWC or LFN cast bullet. I like my XTP's at 1200 fps or a little faster to ensure good expansion.
Larry