bigbulls

First, welcome to the forum.

Second, none of the cartridges that you have mentioned will do anything better or worse than the 7mm STW that you already have. Unless it was a borrowed rifle. If that's the case, then any of the magnums you listed will be more than enough gun to handle any animal you would encounter.

IMHO the ultramags are do absolutly nothing that the standard and new short magnums can't do just as well within any reasonable distance (up to 400 yards) that any normal person would be shooting at game. One thing they do very well , however, is offer up substantially more kick on the shoulder and burn a lot more powder. The ultra mags are over bore in the 7mm and 300 without very long barrels. Those huge cases and huge ammounts of powder are much better suited to 338, 375, etc.

This being your first "magnum" rifle I would highly reccomend the 7mm rem mag, 300 win mag, or the same calibers in the WSM's. The two "regular" magnums will give you an advantage of getting ammo just about anywhere you want but the short magnums aren't too far behind on that now. Walmart is even carying the WSM ammo.