I don't mean to be ironic, but so far this discussion is like a...... is saying: "I'm 5'11". Is it ok to buy on Ebay running shoes size 11?". Most replies advised him to buy the size 11 for various reasons.
Maybe the size 11 is right for a......, but most likely it's not exactly his size. If his shoe size is smaller, he'll be able to walk, but not to run. If his shoe size is larger, he'll not even be able to walk too far.
Best advice: measure your shoe size, then buy accordingly.
In this case, good money management means to buy the right size in order to be able to concentrate only on running at your best.