I'm not sure you could go wrong with any of the above actions. If I were to build a .338 wizzzbangerrrr I think I would like to build it on a Surgeon XL action...my gunsmith would get to have an opinion too...
I have a stiller TAC30 that has performed VERY well for me. I have played with a Bighorn and it was, without a doubt, the smoothest action I've ever cycled. That rifle shot like CRAZY, too.