Forum Thread: Asterisk open-source PABX

Are anybody using the Asterisk open-source PABX? I would love to hear your experiences with it and your setup. I have lots of experience with a big proprietary vendor as a support and installation engineer, and is starting to explore Asterisk on my own. It is a very flexible system with nearly unlimited potential with regards to features, but I would like some users to comment on the actual production quality of the system, what they invested in the system and wether they think it was / is worth it.