Most of the reviews scared me as they were mostly one star. I did have a couple of issues where my ticket was said to be issued on X date before the event, but was not. I called them, and they told me that my ticket would be issued through an app called Flashseats. They ended up contacting the supplier and the ticket was transferred. Got into the game just fine.
This review is mainly here to say that I ended up having a fine experience. I'm not one to stress though so it wasn't a big deal that the tickets required a phone call to acquire... as long as I got into the game.