Where are you looking for carbon deposit issues and how are you looking for them?For the last couple of years, I have been using Pennzoil Platinum Euro 5W40 which has the LL01 approval in my Cooper S with the N18 turbo engine. At 52k miles there are no apparent carbon deposit issues.
I'm not sure what the connection is between Longlife-01 approval and carbon deposits either. Can you explain that?