I had one of the older square slide 10mm's.
I never heard of any problems with these ones.
In the last few years they've been offering them with a new "streamlined" type slide that's rounded off.
As the pics from the AR15 thread show they took off quite a bit of metal.
It appears that this change has severly weakened the slides and caused cracking issues.
I had seriously been considering getting another one in the Wonder-Finish because I liked the look of the new contoured slide, until I heard of the cracking issues with them. Now I kinda wish I had kept the old square one.
Oh well I think I'm all done with EEA and the Witness pistols.