I ran 'opkg upgrade' once and it deleted itself.

I've run into lots of other annoyances with it (e.g. its database is rather slow), but that's the one that sticks in my memory.

opkg upgrade can brick your device.

>Sure, it's no aptitude or pacman, but you have to remember that OpenWRT is a full fledged distribution (package manager and all) that fits on an image of less than 4MB!

It's nice when resources are a limitation. But that's not the case here.