I agree.
I think that some of the pictures I've seen of this figure make it look absolutely fantastic. Some make it look like the Hulk stepped right out of the movie and into a Hot Toys box.
But others... the way the figure is posed... or bad lighting... and sometimes, it looks like a "Hasbro figure". Figures with arms that work this way don't have armpits... just the underside of a ball joint. So when you raise the arms up high... something doesn't look right.
Oh agreed. Arms down with this guy. The walking poses or arms low and ready to grapple poses look the best so that's what I'd go with to minimise the joint exposure and also to not draw attention to the fact that the chest muscles/shoulder muscles etc obviously do not move with the arms in a natural corresponding fashion.