We've been a Kerio partner for years and have deployed much Kerio Connect. Now we're looking at beginning hosting groupware for our clients and are wrestling over the right backend.

Kerio Connect is fantastic, but we have a couple gripes:

• Kerio is often weeks behind on releases to keep up with major Microsoft and Apple updates that break functionality or at least impede new Apple/Microsoft features in their desktop clients
• We've been worried that Kerio has a historical habit of corrupting Apple's Open Directory; we know this happened years ago, and have suspected it happening earlier this year
• There's always some one or two features that are buggy in Kerio, in every release. These usually aren't dealbreakers, just annoyances.
• Kerio does not have any kind of HA feature set

How does Zimbra compare? What are your gripes?

Thanks!

noam