APC is actually integrated into PHP6, albeit disabled by default.
From the meeting notes where it was discussed:
http://www.php.net/~derick/meeting-notes.html#add-an-opcode-cache-to-the-distribution-apcFor that matter I've been using APC & FastCGI on servers I've been carrying out some extreme stress testing on and I've yet to see it crash, with php scripts both tiny and large (128Mb+), short and long running, but that's just my experience.
Post edited by: Twirrim, at: 2009/11/19 19:24