I saw one at an FFL when I was up in Seattle a while back, but ordered one online.
As for the "mystery metal", bottom line is it is a .22 and they often use light metals (zinc alloys or other pot metals). I don't baby my guns, but I'm not exactly "hard" on them throwing them in dirt/rocks etc. Plus, this is just a fun range gun for me.
I haven't noticed any issues so far. If the slide cracks, I'll contact their warranty department, but I'm not concerned over it.