This is a VERY hard question to answer The Webley Service is definitely up there but so is a pre war BSA, particularly one fully decked out with original aperture sights. 1950s and 60s Crosman Pellguns such as the 150 pistol and 160 rifles are also favourites. Onto more modern guns and for build quality as well as fiddle and fun factor, the Baikal Makarov takes some beating.

I could not possibly choose one over the others

John