I personally ride and trust a 1/8" Z-chain (although the packaging says supercycle up here) and have never broken it. In fact, I've never broken any chain. Once, when I didn't have proper chainline and had a 1/8" chain on a 3/32 6-speed freewheel under singlespeed tension, my masterlink clip thingie got caught in one of the adjacent cogs and it ripped (the clip) off because it was too wide, causing the thing to just come undone. Now I just get ride of that part whenever I buy a new chain.

But on my tarck bike? Skidding from a high cadence, dropping off curbs into a skid, running it too tight, all kinds of abuse, and it's still in one piece. In my experience chains have at the worst fallen off, never broken.