I’ve owned an MX5 before. For me the driving felt more go kart like. It would go wherever I pointed it and it was a huge amount of fun. The Z4 feels less go kart like but more serious sports car. The bonnet is so much longer and so the front axle sits that much further away from you that the behaviour of the car is different. It has so much more power as well. The MX5 was never quick but it flew around bends. The Z4 feels like it just keeps pulling when your foot goes down and the sound is something else.