I have a couple of both...and for all practical purposes, there is no difference!
Case in point:
This group measured around 0.489-inch, for 5-shots at 200-yards
It was fired using a Ruger 77R in .25-06 Remington with Leupold 10x optics
Case: Remington
Primer: Winchester WLR
Powder: 52.5 grains of H-4831
Bullet: Sierra 120 grain Hollow Point Boat Tail
Velocity: 2922 FPS @ 15' feet from muzzle
This group, which measured somewhere around 0.303-inches for 5-shots at 200-yards.
It was fired using a Ruger 77R in 7mm Remington Magnum with Leupold 12x optics
Case: Remington
Primer: CCI-200
Powder: 64.6 grains of RL-22
Bullet: Sierra 168 grain Hollow Point Boat Tail
Velocity: 2943 FPs @ 15' from muzzle
Now the kicker...
The .25-06 Remington killed an antelope at 704 yards with a single shot.
The 7MM Remington Magnum killed an antelope at 725 yards with a single shot.
The .25-06 Remington took a white tail buck with one shot at 25 yards.
The 7MM Remington Magnum took a white tail buck with one shot at 22 yards.
Granted, the 7mm at 2943 FPS has more "energy" than the .25-06 at 2922 FPs, but the most important factor is to know your own limitations, and to put the bullet where it counts!