Feel like this is going to drag on now....
Took it in this Morning, took the rs specialist tech out in it and explained that for the first 20 mins or so of driving it pulls fine and then starts to hold back, showed him it holding back and the rs monitor showing it being down on power/torque/boost.
Came to pick it up.... Nothing wrong with it sir etc etc, showed me a print our from their diagnostics with the boost and everything ok, asked if it was done at the point where the rs monitor starts to show low readings "I didn't have the rs monitor on" "well how did you know it was running with the fault I showed you and described" felt like i was banging my head against a brick wall. Service manager came over and I explained the whole situation to him including the videos of the rs monitor showing it holding back, there was the suggestion the rs monitor isn't accurate so I asked if they had fixed that then if they thought that was the problem, no sir.
They'e now taking it further to Renault UK to see if they have a solution, I suggested they take it out using the RS monitor to get the readings from when the fault occurs, failing that I will have to pay to get it on a rolling road and get print outs to prove the problem. All getting a bit frustrating already!
On a side note the i30n performance pack was a cracking drive! Quick, sharp handling and really sounds the part in N mode!