Exchange/Outlook to Zoho Mail

Exchange/Outlook to Zoho Mail

We currently use Exchange for our Mail Accounts, and Outlook (local, not 365) for email. We are a small company of 15, but absolutely live in email exchange info with clients. I am about 4 months into implementing Zoho, and feel that live would be much easier if we could move to Zoho Mail. I would love to try it just with my account, but apparently that can't be done. Our contract IT guy is absolutely fighting me on this - he hates Zoho. My questions are this:

1. Have any of you actually switched from Exchange to Zoho?
2. What are the benefits to doing so?
3. What are the drawbacks of doing so?
4. What are the dangers of doing so?

My biggest beef is the lack of a true central calendar in Zoho. It seems we have to double work by putting things in Outlook Calendar because without Zoho Mail, there really isn't an option.

Any input would be appreciated. -Craig B