I've shot deer and elk with rifles chambered for both cartridges. All I can say is everything hit fairly died...didn't matter if it was a 140gr .284 bullet or a 150gr .308 bullet for deer, or a 160gr .284 bullet or a 165gr .308 bullet for elk.

If push came to shove, I think I like the 7mm-08 better at longer ranges than the .308, but that I think is purely subjective.

Either will work just fine for deer to 300 yards or a bit more. I have noticed, however, that the 7mmm-08 kicks less...noticeably less.