Problems with email

This is the second attempt to post this to a forum. My first post seems to have dispapeared.

I just signed up with Zoho to test it out for my business. I have set up email, but I am hitting too many issues that I cannot work around. All of these issues are critical and would disrupt the flow of business. Without resolution on these, I cannot justify paying for an account.

Problem #1
- Can send email from Zoho to gmail.
- Sending from email to Zoho - shows up sometime, but not all the time
- Sometimes shows up very late (as in, 20 minutes late), or not at all

Problem #2
- All incoming mail from my myaccount@gmail.com account is going to spam (when it shows up, see problem #1 above)
- myaccount@gmail.com is whitelisted in the spam settings

Problem #3
- Account is set up in Thunderbird, but will not download any email from inbox on server. Mail is there in the inbox on the server. I get no errors. Thunderbird just won't download it.
- iPhone is set up with exactly same settings, and iPhone was downloading email

Problem #4
- Sent email from zoho site on PC to gmail
- Mail was delivered successfully to gmail mailbox on iPhone BUT:
- In the zoho mailbox on the iPhone, a copy of email showed up in INBOX for fusionmobile on my iPhone (not reply, but original message). Wouldn't this go into "Sent" folder, not "Inbox". I checked on the zoho website, and that message is in "Sent" not "Inbox" (which is correct). But why is it showing up in Inbox on the iPHone?

By the way, documentation on setting this stuff up is not clear. For example, I only found pop account settings for email clients in a forum posting. Why not put that informaiton right in the settings section of the Mail app? There are other documentation and setup issues, but too numerous and small. Not critical, but enough to be annoying and slow down setup of a new account.

If I was to compare Zoho to Zimbra, so far Zoho has failed.