I believe that the axle ratio and gearbox changed in the 4/4 in the last 5 years. The more recent ones are nicer to drive.
Agree about the recent 4/4 being a nicer drive. The MX5 gearbox was introduced in this model in late-Summer 2012 - it gives a much nicer quality and faster gear-change than the previous Ford unit. And you do have to change gear a lot to keep a 4/4 "on the boil"...
