Top burner element

I recently found an electric stove top burners with different size heating coils. Although the model and serial numbers ( that I gave you ) are not the same as the one that I looked at. SORRY
The customer had 2 different size 8″ burners. By that I mean, one had 5 rings and the other had 6 rings. I think the 6 ring element was 2600 watts.
Does this create an electrical problem or danger? I would think that the 5 ring burner uses less wattage than the 6 ring burner???
I refused to touch her stove because of possible liability. But told her that I would find out if it is SAFE to have 2 different ring size burners. And if there are possible issues with the ( wiring, recepticals, and infinite switches)
Please advise.
Thank you