My understanding on the Premium Only Recommendation is that Premium is not required to make your car run. It is only required to give your car the horsepower of which the automaker brags. I believe they call it "better performance," at your expense. So, unless you need that additional 30-50 hp, you are probably good to forgo the pricey premium gasoline.
Disclaimer, I am not an auto mechanic, but I did own an Acura Legend for ten years which required premium gasoline only, and probably filled it with regular gas 80% of the time. It was noted in the car's handbook, that it could run on regular gas.