7mm-08 has a little more flexibility toward the heavy side of bullets, .25-06 has the same toward the light side. I shoot both of them in the 100-130 grain range.
Both kill like a hammer inside 400 yards, so I would say pick based on whether you prefer short or long action rifles.
how is that 25 outside of 400?
Couldn't tell you, as I have never killed an animal further than that. Exit wound on a big mule deer was about 3" in diameter at 328 yards (angle corrected), and he hit the ground.
I saw another hunter shoot at a similar distance, also .25-06. That shot broke both back legs and kept going. That deer had his chest behind some brush, but was on his way off the ranch. First shot put him down, next finished him.
If I knew I would be shooting 400+, I would take a different caliber just for the energy retention. Probably would go to 7mm Mag, or .280 Ackley in that case.