I have the next gen seats, and last week was able to try the premium seats in a P100D for a full day while my car was in service.
During my spirited drive up in the hills, I felt that the premium seats had much less lateral support than my next gen seats. It seems like a downgrade, despite the premium seats being perforated and ventilated.
Recaro has been in the business for decades so they know how to make a damn good seat! I'd push for the next gen if at all possible.