The .30-06 is a good round. I have a 7 mag for my cannon, though my .308 or my old .257 Roberts are my favorites. Last 10 years since I won it at a gun show door prize, my Remington stainless M7 in .308, it's about the only one I've taken to the stand. I've killed hog, coyote, and deer with it so far. It's a great all around gun for my uses, light, handy in the blind, 1 MOA accuate, and military surplus brass is cheap on the Midway site (I reload all my rifles and handguns). It's a sweet shootin' gun and, frankly, will kill anything I'll ever hunt. Not sure it'd be the best choice for a moose, might rather use my big 7 with Nosler 160 partitions, but it'd do the job, I think, inside 200 yards with my Barnes X loads. Of all my guns, of course, that old .257 has killed the most deer, but it's light for anything bigger. I shot my first deer at age 11 with it, my grandpa's old M722 Remington short action. I load it to near .25-06 ballistics and it's a handy little gun and makes a good long range varmint gun, too.
I guess exterior ballistics and effectiveness of medium sized "deer" rifles is the most debated subject in the history of the gun world, but when you get right down to it, most calibers are quite similar. The .30-06 isn't quite as flat shooting as the 7 mag, doesn't have the velocity or energy of the 7, but I don't think the Moose is gonna know the difference at any reasonable hunting range, inside 300 yards. Hit him with an appropriate bullet in the right place with either and you got moose steaks for a while. The .300 mag shoots harder yet, but a moose can only be killed so dead. Dead is dead.