Not sure I could say it a must over the BvS, depends on what price you can get them both for I guess. There are differences outside the cape but, to my eye at least, they are subtle. The grey appears only a touch lighter and there is more of that gold colour in the suit. Whether mine has a defect I don't know but you can see clearly the black outline around the bat symbol is less pronounced on the SS figure and offsets some of the contrast gain the lighter grey brings.
The material looks a little more matte and rough where the BvS suit appears smoother.
The middle buckle of the utility belt is more of a solid gold and less weathered than the BvS version. All the segments of the belt look nearly identical.
The cowl is undeniably better regarding the tab not sticking out. I believe there are fixes for that but it's good not to have the hassle. SS cowl seems to reflect a little less light back to but probably varies a lot between figures.
Might just be my eyes
but the thighs look improved. Just a better proportion to them. The abs stand out more on the SS figure also. He looks more barrel chested but again that might just be a result of the different paint apps.
With the cape extended he does look pretty awesome and the cape works well. In a standing pose I hate working with the cape, but it's an easy swap for any of the great non wired custom capes out there or the better wired capes.
Sorry for the bad pics, no DSLR camera here and lack of daylight doesn't help. BvS figure on left, SS figure on right in all pics.
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