Upgrading to Zoho Mail

Upgrading to Zoho Mail

We are considering upgrading to Zoho mail, from our current host site which is not Zoho.  Will this be a painless process?  We use ZCRM now with mail add-on and would wish to make minimal changes to our current configuration. Curious to know your thoughts, and necassary requirerments to make this happen.  Thanks in advance, we love Zoho!