Return base iPhone 17?

Had my Mini 13 for years for the small size, finally time to upgrade for my birthday. Got the base iPhone 17 due to reviews, but can’t shake the feeling of how comfortable the Air was to hold. Compared to the Mini, the 17 seems unwieldy and blocky. Whereas the Air might be an inbetweener?

Will the store be pissed if I return the 17 after using it for a week uncased? Or I could buy the Air before returning the 17 and use them side by side for a few days to make an informed decision? I feel rather guilty for this sort of wastage?