I am not sure if this is the right Forum.
Due to an outage of my system I started investigating SCALIX. This is simular to Zimbra.
Here some experiences that I like to share. My personal feeling is that Scalix is faster than Zimbra. The German translation is excellent. But there is no anti-virus nor anti-spam integration. You have to do that by yourself.
About the pricing: There are 25 poweruser included e.g. Outlook and Evolution connector. But no iSync connector.
So as I have only few users I get the Outlook connector free of charge. I think ZIMBRA has to think about theit licencing policy.
My personal feeling is that Zimbra has some advantages. But for small companies Scalix the the better deal.