Wombat said:flac itself is totally stable. (still don´t know why it shouldn´t)
It has the advantage to be usable on multible plattforms, like PC and Mac...
Yes, since it is open source freeware done under sourceforge
it is likely to be very stable and good. It may sound cynical,
but for PC at least, I would say that the best and most reliable
programs are freeware and often open source and the worst
and least reliable are the most expensive commercial ones
(need i say M$).