Is it only the manual that has the sports suspension then? I've seen one on ebay at the moment (1996 model) where he claims;

M-Sport suspension as standard, there is no mechanical difference between a Sport and Standard model, just body kit/spoilers etc. All the car really needs to make it look identical to an early 2000>on spec is the front and rear bumper assemblies.

Is this true or is he just trying it on to make his car sound better?

I see no info for a 1996 5 Series....I'd be a little leary of that guy.