I've had two of the boat paddle Acura stocks,and I brought one of the Acura thumbhole stocks in the 45 caliber 22 twist this winter, I target shoot a lot, and I walk and hunt a lot, I also have the 50 cal mr 50 cal Acura, that is the stock that you want, the boat paddle and the thumb hole both transfer recall into the shoulder and down into the body, the mountain rifle has a straight comb the recall come straight back instead of back and down if that makes sense it is a more manageable recoil in my experience,I have a target range Right out my backdoor and I shoot three or four days a week a lot of bullets so I'm very real cool sensitive, I think the thumb hole looks groovy but it ends there to me as far as function,I will probably give my 45 Cal thumbhole stock to a friend or else sell it soon very accurate and I love the twist but I cannot stand the stock,I find the thumbhole stock when you're gripping it about to shoot pivots to the left or right very easily too easily for me and I guess that doesn't make sense you have to shoot a lot to understand what I'm saying,I'm a CVA fanatic but I'll never buy another one that doesn't have the straight comb stock