Objectively...
The objective factors to consider are:
1---
Does one shoot better with a "pistol grip" type of stock, whether it be a pistol grip or a thumbhole stock? It is likely that arguments can be offered on both sides of the discussion, but it must be noted that almost all modern military rifles now have a pistol grip. This is likely not purely coincidental. The ergonomics seem fairly obvious.
2---
Does one control recoil better with a "pistol grip" type of stock, whether it be a pistol grip or a thumbhole stock? It seems that the answer is likely yes, which could be both a plus, or a minus if the riffle has enough recoil to dislocate a thumb. Luckily, hunting calibers, in rifles of proper weight, likely do not generate enough recoil to do this with shooters who handle their rifle correctly and firmly.
3---
Can one reach the top safety/cocker/decocker easier without a "pistol grip" type of stock, whether it be a pistol grip or a thumbhole stock? It seems fairly impartial to observe that: first, the thumbhole stock requires a more convoluted thumb movement than a traditional stock, but that, second, the R8 safety/cocker/decocker is not used as a typical shotgun sliding safety unconsciously pushed forward during a smooth shouldering. So, this may not be an issue, although, clearly, almost all modern military rifles have the safety/selector conveniently located within immediate access of the thumb, and this too is likely not purely coincidental.
4---
Does one shoot repeat shots as fast with a "pistol grip" type of stock, whether it be a pistol grip or a thumbhole stock? There is materially an upper bridge (above the thumbhole) in the R8 stock, that the thumb MUST go under. Is there a risk of putting the thumb above it (rather than below) in a rushed reload during emergency self-defense shooting? The answer is likely yes, but extensive training and familiarity is likely to be also part of the answer and may entirely alleviate the risk.
In the end, as in most things related to hunting rifle choice...
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The plain old reality is that shooters do better with rifles they like and trust, rather than with rifles that may be objectively better but that they dislike...