Now everyone know that even Tsipras invited the Greek people to vote no regarding the agreement with the European countries and even its people followed it, the agreement (more severe than that which was did not accepted from the Greeks) was signed from all the parties. With this news talking about the question made in this thread is in vain. But I think that the risk that Greece leave EU is not totally goes away forever. The agreement signed is not definitive in the meaning that will solve the principal problem of The Greeks (the debt). Because the debt of Greece, as it is and as much as it is, according to IMF, is unsustainable. In this meaning, after this agreement needed other agreements in which must be restructured absolutely it. And no one knows which will be the position of Greeks and its politicians. So, to conclude, the story exit of Greece from EU is not yet finished.
Having this in mind has meaning to come again and comment at the question of this thread. The advantages and disadvantages for EU if the Greece go out. To speak about everything that implies that act in an post is impossible because the question is to complicate and need to much analysis. But who want to know deeply the question I invite to read this two articles from the prestigiouses BBC and Der Spiegel.
http://www.bbc.com/news/business-31457991
http://www.spiegel.de/international/europe/what-a-grexit-would-mean-for-greece-and-for-europe-a-1019542.html
There are enough an sufficient to understand the matter in all its complexity.