Okay so I got the 50 loot boxes.
My results: WAY too many blues and whites. Repeats were even worse. Zarya's cyber skin keeps haunting me with repeats.
But I got Jazzy Lucio and Graffiti Tracer plus Mercy and Tracer's dance!
I need 75 more coins to get 12,000. Then I can buy the 4 remaining skins that I need: Genji, Soldier 76, Bastion and Symmetra.
I wanted to get all the dance emotes too but it looks like that won't happen. I'll probably buy 25 more loot boxes and hopefully get enough for both the 4 skins and at least Genji's dance.