How far is far? If far too you is 300yds then I say flip a coin. If you are concievably going to be shooting at 400-450yds then I say go with the 7mag. A 140grainer in the 7mag is 7" or so flatter at 400yds than a 150grainer from the 30/06 and it has more authority to boot. I have two of each caliber and they both are some of my favorite guns (oh heck who am I kiddin, I love ALL my centerfires! ) but if I had to pick only one of the four I would stick with the 7mag. But then again I am a "magnumophile". Both cals have an extensive offering of factory ammo available for them, the 06 being THE most popular big game caliber on the planetand the 7 being THE most popular mag on the planet. For the reloader their is a plethora of both 30s and 28s available, pick your poison.

Like I said, inside of 300 yds all the deer I have killed with either couldn't tell the difference!
RA