In this day and age I wouldn't think there is a significant reason to choose one over the other. The performance of today's 308 Win certainly meets, or even exceeds, what the 30-06 was when it earned its fine reputation.I haven't shot an elk with either, but plenty seem to do so without complication. Dead is dead. I can say the 308 has been very easy to load for in a couple different rifles and makes a very pleasant to shoot rifle. The only reasons I'd ever choose the -06 would be to shoot heavies, or for sentimental reasons.
