I finally got some time behind mine that came in the initial order. It only took me a year or so to get it mounted. I tried when it came in but it needed a significant amount of material removed forward of the recoil lug to get the action to seat. I have one of the now "limited edition" bare carbon so the fit might be fixed for newer stocks.
In short, I'm pleased with the ergonomics but might need some spacers for my ape arms. I have low rings on the action it's currently in and find it comfortable for now but I may adjust or try medium in the future, especially if I run a check pad/pack, which I prefer for hunting.
Based off my limited time behind the rok stok I'd like to purchase another for my new build.