As far as branches of the military go, not to spark a debate, I don't think one is better than the other.
Different, yes.
Better, no.
You still fight for the country and our rights whether you're getting shot up on land or in the sea.
The training is different
The atmosphere is different
So in the end it comes down to you find the army or marines more favorable.
But there's nothing written or proven as to which one is actually better.
Because we're on the same side.