nothing in the homebrew world is ever stable. Custom Firmwares are not stable. I bet all of us has had at least one issue with them in the past year. For me that would be the sleep bug. It's unofficial, but being released by a guy we all know as a great guy, wally. He'd never 'brick a psp on purpose.' I respect the fact that you're being careful about an unofficial release, but remember what I said, nothing's ever 100% stable