Re: 7mm Ultra Mag or have you seen any similar ballistic performance?
Better is very subjective. If all you want is the max velocity, go with the 7 RUM or a necked down 30-378 or the Lazzeroni. I agree that the RUM's are VERY ineffecient, but velocity is velocity, if thats what you want, you will get more with the RUM and other wildcats than the STW.
Long range shooting is a process that ends with a result. Once you start to focus on the result (how bad your last shot was, how big the group is going to be, what your buck will score, what your match score is, what place you are in...) then you loose the capacity to focus on the process.