I had it installed for a while, and there were fairly frequent crashes (i.e. about once every 8 hours of reading) requiring a reboot.

But it was _almost_ worth it. It's a really great reader, especially for reading PDFs.

After some software update about 6 months ago it got halfway uninstalled somehow and I did a factory reset and haven't reinstalled it yet. I recall reading that it's not on KOreader's side, and they can'tfix. :(

It's been perfectly stable for me since I got the device a few months ago, but I also don't read for hours at a time like the other commenter. It's possible that it leaks memory after viewing several hundred pages or something like that.