I have discovered a nice work around:
I am using Office 365 Home (4 users) which does not include Outlook 365, it uses Outlook.com.
Outlook.com is the new Hotmail and has a few limitations like about 100 emails sent/day.
It has unlimited mailbox size.
I created a Send Only account in Outlook.com using my domain email address and configured it as the default send-from address. Then I created an alias to my email like ******@Outlook.com
My domain was hosted with Google Apps and the DNS records at my domain provider pointed to Google.
I reset the DNS records at my domain provider to default (using Netfirms) and reset the SPF record.
Then I created 4 forwarding email accounts (no local mailbox) for my domain at Netfirms that forwarded email to my Outlook.com aliases.
Using POP3 with Outlook.com is slow as only 50 messages are received every 30 minutes which is not practical for most users.
Email is forwarded from my domain provider to my alias.outlook.com email address and arrives in my Outlook.com mailbox looking like it was sent to my proper email address. When I send emails, they send through my domain provider, so they are not send "on
behalf of".
Sends and receives are fast and act like they are hosted on Outlook.com.
I needed to create a dummy mailbox at Netfirms to use for sending mail, because the forwarded emails did not have a username/password associated with them for authenticated SMTP. So I send using
******@mydomain.com with the dummy username and password.
So for $99/year, I have 4 users with 1TB of OneDrive, Office online (free) and Office 365 apps, and mail running on Outlook.com