My zavvi edition finally arrived today. A small comparison between the us and uk version:
The colours of the us version look a bit oversaturated (Buckys face is pretty yellow) and details get lost because of that. But this also means the line through caps face is less noticeable compared to the zavvi version where it continues straight through. The border has also a slightly different colour tone (again the us version is a bit more yellowish).
Same goes for the back, the red is more saturated which makes the shield in the middle pop out a bit more.
Both are great editions with their cons and pros