same problem as im having, but mine is because i just got used to having a nearly new corsa lol. i'm going to be swapping my gearbox oil, and then either leaving it if its better, or looking into changing the gearbox mount.
Happens in all Clios to my knowledge. Wouldn't really notice on small petrols as there's no torque, but on the diesel for instance there's a good inch or so of movement when nailing it.