The service is growing and seems that is going better with the new version, I bought the Tier 3 to have access to an upper plan with the majority of service in the web app. Now it do not express the existance of any specific plan but all that I have the tier 3 and the service seems that are coherent with the Business (the tier 3 was the businees in the early stages when I did the payment) so it seems enough ok.