looking at cyl #1 from the top (which was one of the most intact cylinders)
looks like its hit a valve on the top right?
[attachment=59146:IMG_20140518_132212.jpg]

This is the piston from cyl #3 where most of the action took place:

[attachment=59147:IMG_20140518_133901.jpg]

others:
[attachment=59148:IMG_20140518_133927.jpg]
[attachment=59149:IMG_20140518_133951.jpg]

 

Yea, that is definitely mild detonation, causing the rings to shatter. Over time the ring pieces worked their way past the piston lands into the cylinder. the worst thing about this is that if you are turbo the ring pieces then crash into your turbine wheel and pretty much destroy it as well.

I has the exact same failure when my wastegate line popped off. It only detonated for less than 2 seconds and the damage was done.