Whitetail in Tennessee .
I prefer the .257, l have taken coyotes to an elk, and am very impressed with it
But really any of them from the 240 to the 7mm would do just fine on whitetails.
As far as model, the lighter models are nice to carry and shoot good, but the barrels heat up fast at the range.
Heavier models are not as nice to carry, shoot good, and for me are more balanced to hold and shoot.
It all comes down to what you are looking for and type of hunting you do, stand hunting or still hunting mostly
Good luck on your choice.