I have been using zcs for 2 weeks now and want to have it full operational as production server. We currently have qmail for our organisation which I want to switch to zcs. I have few querries:

1. Can I use zcs for production environment without any downtime/problems?
2. What is the intigrity of zcs?
3. Can I completely rely on zcs for our mailing solution?

I am being little skeptical as I do not have any previous experience with zimbra and we cannot afford to have our mailing system down and suffer our business.

Thanks & Regards,