How does that case feel in your pants pocket, and also while moving about sittng down, getting up?
Better to buy a 6+ and return it for a 6 than buy a 6 and try to get a 6+ anytime soon.
Now you can make an informed decision over the next week or two.
I wouldn't return it because of my own decision. I would rather try to trade someone or sell it and lose money. Just seems mean to return something that doesn't have a problem.