On a puny netbook. Yes, F12 is pretty stable.
(I'm cheating a little, because this netbook goes to sleep every day.
But still...)

I found Fedora 12 very stable throughout its lifecycle, and enjoyable to use on my netbook (ASUS 1005HA).
I skipped the 13 release and now have 14 on it, though I must say it does 'feel' a little slower. Other than that, I've had no issues with it.

Take Care and Be Well,

Landor