I don't know anything about the Aetec, but a 338 Magnum would have a little bit'o'recoil. If you get a scope make sure it has a good eye relief. Maybe 4" or 5" at least.
You will also want a scope that will hold its zero under heavy recoil. Lots of "more affordable" scopes won't.
I handled a Nikon Omega once, they seemed pretty nice, over 5" eye relief, no way you will be hitting your eye with that.
There are lots of good reviews on the SWFA fixed power "Super Sniper" scopes.
www.swfa.com
You can search and find the reviews easy.
I own one and my only complaint is the turrets are a little mushy. Mind you this is only between 1/4moa incriments. But I'm not benchrest so I dont't mind so much.
They are the quality of a $800 scope, but they only cost $300, $400 if you want the 3 turret military contract one.
Anyway, all this typing about the Super Sniper is becasue they are very rugged and hold their zero, and have accurate inciments. I know they use them on Barrett 50's since they hold up very well with the recoil.