When I used to spar, I hated getting uppercut-ed. Most of the guys I sparred with were shorter than me and hadn't really understood the significance of body punching, but on the rare occasion they threw an uppercut, it hurt.

I've been hit by Jabs, Crosses, Left Hooks (those hurt too), Overhand Rights, and Right Uppercuts, and the Uppercut hurt the most for me. Haven't taken a hard body shot, but I'm sure it hurts much worse than an uppercut.