Coil pack was indeed faulty - thanks so much for all the input.
You know what? We checked the ignition on the oscilloscope...Cylinder 2 was indeed slightly 'iffy' but I dismissed it at the time as the car appeared to be running fine (when it was running...) Schoolboy error, eh?!
Lesson learned for me there: "Mr Customer, there is definitely an abnormally with your ignition. As part of this repair process, we advise a new coil pack and plugs as a first course of action. By rectifying this fault, there is a good chance the cutting out issue will also be cured...."
Thanks again chaps,
Andy
