Sir,
When I bought my encore years ago I bought the TC thumbhole grip for it and loved it! Later when the prohunter line came out and the new thumnbhole grip became available I bought that and switched the two because I wanted the new one that has the nice recoil pad. I've owned both the synthetic new prohunter & old regular thumbhole stocks. Buy it!! When I put that rifle to my shoulder it's an incredible fit for me and so very comfortable & nature. You're going to have to move your thumb to cock the hammer regardless of what stock you have and I wouldn't worry about it anyway.
*My only complaint and this is being very very picky.... The stock can be a little slippery in the hands and can tricky to get a good grip on the gun. I'm not saying it's a poor design, just that the plastic is a little smooth. I'm going to wrap some friction tape on mine some day if I ever remember.
Overall the thumbhole stocks are an outstanding fit for me, but that's always subjective. I would rate it 5 stars out of 5 and I'd buy another one if I had to do it all over again.