HI mate, this topic could go a few ways lol but your going to get a few opinions I think, most if it will be personal preference.. For me though if your into replicas and have not got one in your collection go for a blowback BB pistol
But definitely a BB rather then pellet to keep realism, also go for one with a full size drop out magazine not a stick type, or one with a trigger indexing system..

Personally I think everyone should own a 1911 lol..

Have a look at my YouTube channel if you like your see a good few choices.

ATB Marc