I'd like to say I'm shocked to see those cracked discs, but it's all too common. For race cars, where you can ditch then after 1 use fine.. but for road, they're just doomed to failure.
Animal, they use 1 common caliper for all 4 pot kits, but please don't go out of your way to get them. It was a bit cheeky of me to ask to be fair.