ok, out to get morning papers, rechecked tyre pressures and found one at 30 psi and others 34psi.
Set all wheels by hedges reccommendation of 39psi (2.6Bar) and seems to have improved it slightly but still not great.
accelarate from 70mph to 90ish i get the feeling the balancing is wrong, i can feel ever so slightly wheel shake, but travelling at a constant speed is fine at ANY SPEED, and hasnt lost any performance, so coil pack or missfire i think can be ruled out.
Agree with you John_o, 12 weights seems abit excessive, not sure whether to go back to the place that done the balancing or go somewhere else to see if they agree and redo them.
2nd gear accelation is smooth as , holding any speed is smooth, only apon acelarating from 70 and beyond, it happens.