No difference. One is a Coke standard the other is a Pepsi standard IIRC. They both do the same thing. I have a bunch of pin lock types I've been using for home brewing for ages. Infinitely better than bottling or using mini kegs.
As a plus, you can make your own built in Kegerator using these kegs as they are narrow enough for an under bar fridge. I'm using a standard mini fridge under a custom concrete countertop. I just replaced the door mounted shelves with a piece of stainless steel, everything fits quite nicely.
This is in my gazebo: