These cameras basically have the same specs. So in theory they should take the same quality pictures.
The main differences are the physical size and weight and the touch screen versus physical buttons. Plus the actual screen size as well.
Battery life is said to be less than average on the 500. Though you can always carry an extra battery and you might not mind that.
Bottom line- Quality should be comparable on both these cameras. You have to decide what you prefer as far as the physical aspects.
Can you return to Adorama? Buy it and try it out! It's best to decide when it's in your hands and you can try it out.