Thanks for that Graham, it's good to know as so much confusing info about what to rub into it!!! Both my physio be the nurse today (and your research!) recommended E45 so I'm going to go with that and see how it goes.
Hope the E45 helps - I think the main thing is how you massage it, not what you massage it with. So across the scar, and over time you can start to use quite a bit of pressure to get down to the deeper scar tissue. Best to take note of 'proper' medical websites such as the NHS, reputable hospitals etc.