Arch Linux is anything but stable, haha. However it shines in providing updated software, including kernel, as fast as possible.
Are the previous SD-cards corrupted to unsalability? Can you re-format and surface scan them?
In my case it was about luck. First three cards lasted only a month in my Pi. Then I bought a bunch of the cheapest, 30GB cards I could find. I used only one of them and it is running Arch on BTRFS for two years non-stop.
I feel like Arch is fine as long as you never touch a running system :D
The previous SD-Cards are both fine. I could re-format both of them. One is currently in the Odroid and running without any problem at all. I just checked the other one and did a surface scan - no errors. :-/
Great. So it is only a file-system corruption. It could be caused by unclean shutdown, insufficient power input, noise, overheating or kernel bug.