For at least the next two years, these trends are likely to become important selling points in most VoIP vendor-customer pitches. While that's great, be sure to fully understand what's being offered and how the vendor is going to go about delivering it. Is a 5G implementation truly standards-based or are there still some proprietary hardware or software components? Have much will any new security measures affect overall voice performance, and does the vendor fully support the changing security requirements in important industry regulations, like HIPAA and SOX?
This “Product Review” is a lot less helpful that is first appears. It amounts to little more that a list of providers, with no attempt to provide a feature-by-feature comparison, something that a “real” product review would provide. For example, which providers use a phone adapter (a la Vonage)? How many minutes do you get for the plan(s) mentions? Etc.

A virtual phone number is a telephone number without a phone line directly associated with it. Instead of being connected to one specific telephone line, a virtual number is programmed to forward incoming calls to one of the pre-set telephone lines that the client chooses, be it fixed, mobile or VoIP. Virtual phone numbers are also known as access numbers since they can work as a gateway between traditional calls and VoIP.
Website: https://www.onsip.com/voip-resources/smb-tips/business-voicemail-greetings-5-sample-scripts#:~:text=Business%20Voicemail%20Greetings%3A%205%20Sample%20Scripts%201%20Personal,Greeting.%20...%205%20Emergency%20Situation%20Voicemail%20Greeting.%20