RingByName

Pros -  This business VoIP service enables you to quickly sync your Microsoft Outlook or Google Contacts with your RingByName account. Plus, you can choose how long you want your contract to last.
 Cons -  Although you can create a queue for your callers to wait in, this service doesn't have some of the advanced queuing options that distribute calls evenly.
The Verdict - 8.1/10RingByName has a reliable network and all the standard features you'd expect a phone company to provide. It also has some convenient features such as Outlook, Salesforce and Zoho integration.