I noticed that after the latest HOTFIX that this still seems to be unbalanced.
“Test-Live - Solo-Player No mods XP progression settings 1.0x down the line I mounted a Jaguar head and received almost 100,000 XP. I have noticed that mounting any type of head gives a crazy amount of XP to the character. I will test it again. In my opinion, it makes the level progression way too easy. Currently level 47 and jumped to level 48 96,000 xp for jaguar head 96,000 xp for kudo head.”