Mine suffers the same problem,but only does it when it is really cold.Am running a 57i cone kit which doesn't help.On sunday it had warmed up a bit up here,its was going like feck and didn't miss a beat. (ROLL ON THE SUMMER)
Have you tried cleaning out all the breather pipes for the cam housing, like the pipe that goes from beside the dip stick to the cam housing, the pipe that goes from the cam housing to the throttle body, the breather pipe that goes to the inlet manifold from the cam housing. Have you cleaned out all that brown gummy tar stuff from the 2 throttle plates ? Have you had the injectors ultrasonically cleaned?
Two major contributory factors to this hesitancy is excess pressure in the head (i.e clean the breather pipes) and savage induction temperature be that too cold or too hot (cold weather in general, or hot/cold weather with non standard induction)
One point, mine isn't great around town but is MUCH improved by running super unleaded. I don't get it if I'm doing motorway but when I'm at home I get super, reset the ECU over night with RON plug on A and is then noticibly better. Currently trying a tank of Optimax for the first time so will see how that goes!
I did try super once and it felt a lotstronger. I also tried Optimax once and it felt smoother for about three weeks and then the hesitation started. It ran bad so i stopped using it and went to normal unleaded. Once that was flushed through again it felt ok for a few months and now it is hesitating and juddering again.
Light comes on for the couple of seconds at start up but never comes on after that. The only light i have on is the stupid ABS light - Cant get the front wheel sensore out to replace... pain in the arse.