Well, I've never shot an '06 in a 15" barrel, but I have a .308. I opted for it over the 7-08 for the ability to shoot heavier bullets if need be. So far I've only shot 150s, and it does a fine job on feral goats! Don't know about bears, but with a good 165 or 180 grain bullet, you should be fine. I'm not a big fan of recoil, and I can bang away with my .308 (shooting a pretty stiff load of IMR4064) with few worries. I recommend the .308 without reservation for most hunting and shooting in a 15" barrel.