My previous company used Zimbra for 6 month, after 3 months almost everybody switched to Gmail, it was an absolute pain to use back then, after 6 months we got

My previous company used Zimbra for 6 month, after 3 months almost everybody switched to Gmail, it was an absolute pain to use back then, after 6 months we got rid of Zimbra. It was 2 years ago. We're using Zimbra at work right now. It got better, but it's not even close to Gmail when it comes to read/write/manage emails: it's slow, and has numerous quirks. But it has a built-in IMAP & SMTP server, so you don't need to use the webmail. But it's also doing much more than Emails, it's definitely a good alternative to Exchange, but switching from Gmail to Zimbra? I wouldn't even think about it.