1- I had the USA box set and own the Japanese first pressing open matte. I can't really remember but I do prefer the Japanese single disc.
the colors were different, the image was a little more rough in spots but overall the best version, and I do believe that others agree.
2- I had the first USA Vestron and then sold it after I picked up the blood red, while I did prefer the first USA Vestron I wanted to keep the red limited disc.
the widescreen didn't really give that much to the sides and it was pretty much the same on the top and bottom, so it was more of an open matte on the Vestron.
3- I only have the 3rd army of darkness Japanese Captain Supermarket, while I have never seen other pressings I was always happy as it is a longer
version, but I will be adding this to my shop soon as I need to lighten the load of Discs I own.
Hope that gives you a quick summery of these discs.
for 1 and 2 any version should make you happy, unless you need to get all the versions

as for army just get the Japanese version or possibly one of the HK releases?
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