Good for transferring over an existing site. Truth be told, I haven't used it for building a brand new site-- I know that this is a fairly common thing but I just never needed it. For what I've used it for, it has worked well. For a small business with anyone with a little bit of technical skill, it's surprisingly good.
Zimbra is great for an email system for a medium or large organization with appropriate IT staffing. The system is easy to use for end-users, and has a fantastic web interface. Unfortunately, it is overly complex, when considering staffing requirements and price, when compared with Office 365 or Google Apps for smaller organizations. For other education customers, it is hard to compete with Microsoft and Google providing their services for "Free" now though
The password change is not activated when you access by IMAP, Pop3 or Exchange sync. You have to know that the password change is required and you must go to the website to do so.
The management of mail rules should have more checking options.
There should be more applications compatible with Zimbra, the ones that appear in the Zimlets.
We can't really choose anyone else and the cost/effort of moving all of the hosted data would be extremely large, and we just have to stick to them, and hope they improve service
Overall, we were satisfied with the implementation. We perhaps should have spent more time consulting with Zimbra or others regarding best practices but as we got to know the system better we were able to make changes relatively easily after the fact.
We use Wix currently for our online store. It is nice and easy to use, but they don't offer the email domains as well (the last time we checked). They have pretty decent customization of the web page, but still limited. We're going to try it with GoDaddy, since we have other services from them already. It just doesn't make sense to pay two different companies for something we can do with one.
We selected Zimbra because it has a lower cost in the market, offers more development features for its open source, has a very easy to use interface and adjusts to the needs of the company.
GoDaddy reduces our ROI by costing me in non-billable hours. I don't charge clients for sitting on the phone with tech support to power cycle the server or fix the php.ini file, so my $/hr takes a hit.
Their nickel&dime strategy requires I have an additional conversation with clients about their max recurring fees. Small as they are, I need approval for upping their bill. GoDaddy is only the cheap option if you don't value security, stability, or performance.
Since all of our ROI studies and strategies are performed at the corporate level, I'm really not sure what positive or negative impacts Zimbra has had on our overall business objectives. I can say that at least one positive impact it has on my business objectives, in the medical record department, is the ability to be as paperless as possible.
