[mintacular]

Absolutely, while most 5s should be in the same "ball park" there can still be quite some variance within 1 grade category, ie. weak 5 ex's and strong 5 ex's...Centering is one of these big differences and you will see that cards strong for the grade will sell for higher (Also, before PSA added half grades a few years ago there are some cards out there that perhaps someone hopes to resubmit it and get a .5 grade "bump")

Keep in mind that grading is a technical science so 1 issue could automatically prevent a card from reaching a higher grade but it's "eye appeal" is much superior to a similar grade card...The best example of this is that you will see an absolute beautiful pre-war card in every way except a tiny pinhole and therefore the card is automatically a Fair 1.5 or worse, and then you can see the same card that looks like it was run over by a truck a few thousand times with also the grade 1.5 Fair...obviously both are the same grade but the pinhole has greater eye appeal (with most people).

In short, focus on the overall eye appeal of the card inside the holder iand not just the final grade