Mail from my Zoho Services goes to Junk - Possible solution - Multiple SPF Records?

Mail from my Zoho Services goes to Junk - Possible solution - Multiple SPF Records?

During my testing I have noticed that a large number of emails sent by my zoho services are filters as Junk/Spam by outlook and online email providers (Gmail, Yahoo, Hotmail, Live ,etc)

In each instance i have set up the service to send "as me" from verified address at my domain.

I use a number of Zoho Services CRM, Mail, Campaigns, Survey, SalesIQ... etc

During my set up of Zoho Campaigns I read a note on SPF records and their importance with respect to "authorized senders" for mail servers that do not share the same domain as the "from" or "replyto" address.

While I have not yet read anything specific to SPF records for other Zoho Services (CRM, SALESIQ, SURVEY, MAIL) it is logical that these domains would also need to be added to the SPF record for my primary domain for uninterupted sending of mails on behalf of my domain.

Has anyone found this to be true? 

As a test I have added all the mail sender domains I can find for zoho's services (I have not found a single conclusive list)

v=spf1 mx
 include:zcsend.net 
 include:zohosurvey.com 
 include:zohosupport.com
 include:zohodiscussions.com  
 include:zohocrm.com 
 include:zoho.com 
 include:zohomail.com 
 include:zohosalesiq.com 
~all

I'll report back as to whether this makes any difference to the Junk Mail Filtering issue.

Does anyone know of additional Zoho Domains that should be included?