I've used the ProHunter 100gr in .243 for about 25 years. Regular kills at 250m+, longest kills have been 350m. It is accurate enough for me to trust it 100% with precision neck shots in steep bushy country, for when I don't want them to go even one step in any direction.
It has accounted for more game in that time than all the other bullets I've ever used put together, twice over. It stabilises fine in a 1:10" twist, though it can be a bit finnickity to get the load right. I push mine at 2800fps and they are a bloody fantastic projectile, frangible and very deadly, dumps all the energy where it matters rather than punching right through and expending its energy somewhere in the surrounding countryside.
There is no difference in the construction of the ProHunter and the GameKing, they are identical but for the base design. Contrary to some opinions on the interweb, they are not designed to be controlled expanding (ProHunter) vs frangible (GameKing). I have that in writing direct from Sierra!
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