It just goes to show how scopes vary. I have a mk2 which will have to prised from my cold dead fingers. Crisp, clear, sharp and only suffers from lens flare from sun behind target, slightly dark image at 50x in lower light, and slight colour fringing unless your eye is dead centre. I've only looked through a couple of mk1s, both ok but nothing great, and one big BSA which optically I thought was truly terrible, like the bottom of a milk bottle. Worth noting that all were very good rangefinders though.
I think my Nikko was in the first few batches of Mk2s, same as the one Calps has used for years ... though I didn't Hammerite mine!