RingCentral

Pros - You can control your settings through your smartphone. The automated call-distribution queues this business VoIP service provides give you the power to decide how you want to divide the incoming-call volume between your employees. It also has a Find-Me/Follow-Me feature that instructs the service regarding which devices you want to ring when someone calls you.

 Cons - The conference-call options are limited to a three-way call. Additionally, this company provides only the raw data in its reports as opposed to graphs and charts to illustrate the information. 

The Verdict -  9.73/10RingCentral has a reliable, fully redundant network. It comes with the basic features you'd expect to find in a phone service, such as call transfer and e911, as well as advanced features such as ACD queues and Find-Me/Follow-Me.