Well, if both used guns, Eastwood obviously wins. If only swords are used, Mifune obviously wins. I'd give the edge to Eastwood honestly because he's just so damn quick with a gun, it'd be very tough for any man, much less Mifune, to use a sword as quick as a bullet fired by Eastwood could go. Although if Mifune catches Eastwood off guard...

As for Ramon VS Unosuke? Easily Ramon! Ramon obviously knew how to use his gun. I don't remember Unosuke being all that talented with his pistol.