I would probably go with the Remington SPS or Ruger of the two you have chosen. They can all be very good guns but the browning will be the most expensive of the three. Between the 270 and 7mm I would stick to the 7mm for the bigger stuff like elk. Another choice you might look at would be the good old 30/06. It will do anything either the 270 or 7mm's will do just as well. Don't skimp on your optics. I'd rather get a cheaper rifle and more expensive scope than the other way around. The Remington SPS and a good leupold 3-9 are about as good as it gets.

Other calibers to look at, 300 WSM or WM, very versatile rounds but with a bit more recoil.