Just out of interest, the people experiencing losses, do they have piggy-backs or stand alones?
I find with my SAFC II that it goes out of tune after a while anyway due to the stock ecu constantly learning and altering it's settings.
Before I go and get a retune for 98RON I'll be resetting the ecu, using 98RON for at least a few weeks, and then getting the tune redone.
With a stand alone I gather you should be able to dial in some more timing straight off the bat as you are the one inputting the settings into the ecu as apposed to the ecu learning and altering for itself