BMW’s model proliferation may soon be in the same league as Audi’s, as the company is planning a saloon version of the 1 Series. It’ll become the fifth 1 Series variant, joining the three-door, five-door, coupé, and convertible versions.This isn’t official, but the word according to Autocar. It makes sense, if for no other reason than Audi is planning a saloon version of the A3 – the concept version of that car debuted at last year’s Geneva Motor Show.Because cars are getting generally bigger and fatter, the new 1 Series will be pitched as the spiritual successor to the original 3 Series, satiating the desire in some keen driver types for a nice little rear-wheel drive saloon with epic handling characteristics.