Apptivo Premium – Any users out there that can give me feedback?

I am planning to switch from Salesforce to either Zoho or Apptivo. In the first round, Apptivo is more attractive as it is cheaper than Zoho.

We are 4 users, we do send mass mail, we integrate with Gmail, and we want to see when our emails are received.

Any Apptivo users out there that can give me their feedback?