I was asking the same question when I bought into kegging. I have always a been a Pepsi guy, had to say that. I went with the Ball lock, I have three kegs in my Keezer. Here is what I found: It might be just me, but I have a hard time telling the difference between the In and Out posts. I have to look at the worn down writing. With this being said and the fact that the Pin kegs are cheaper and more available, I wish I would have goen the Pin route.