Megane Rs, Shuddering engine fault

Hi people,this is my first post and i need your help,i have a Megane RS, 10 plate its done 27000 miles,problem is when i drive the engine shudders side to side,I've taken the car to the garage where i bought it from, and the keep saying its the character of the car… now it shudders so badly,that the whole car shakes, i have also takes this too two independent garages,and they keep saying its the engine mounting bushes,but renault keep saying"its the characteristic of the car… now the pulley has moved and frayed the fan belt,and the AA advised me not too drive it,as the cause of the problem is the engine mount.. Renault are adamant that its the characteristic of the car…



Please help..