Another point to consider - is it fair that two people who do the same job for the same company, who get paid the same, retire on the same day with full pension entitlement (38 and a bit years) in a defined benefit scheme, receive a different amount per year in their pension? Surely this is no longer a defined benefit scheme anymore??
This is very likely with a cap on pensionable earnings. The fixed pay deal sounds a much better option (not necessarily a good one though!) as it removes any chance of such a strange situation occuring.