some of this may be incorrect because i am not a sip/voip expert
Buying lines can be extremely cheap. You can get 1 line for employee with a per minute plan for 85 cents a month for US with per minute billing in some cases and flat rates can be 4.25 in some cases with no charge per minute.
You can also create 1 line and have multiple employees be available. So you can order a 800 # (which is only slightly more expensive) and then have 5 people potentially answering it. This would also potentially be easy to scale.
You can create a digital receptionist and can have voicemails get sent to email.
Another reason to use voip.ms is if you are doing business development or inside sales and trying to reach people, you can literally just buy a local number to try to reach people in that local market if that helps get people to answer.
Many of the features on voip.ms are charged based on use, so it’s much lower fixed costs and variable marginal cost. That can help if there are fluctuations in demand. For a business starting out, it could be great.
Regarding quality of calls, it can depend on the quality of the Internet. Voip.ms is so affordable, you could really test the quality for a very low amount.
Voip.ms has a lot of features and can be used at a simple level or highly complex level. It depends on whether you want to learn about all the features. I am still learning about some features and don’t understand them all yet, but I am learning more of them over time.
It would really depend on how your business operates as to how much you could save. For instance, if you are doing sales of large items, and really need someone to answer, but don’t do a large volume of calls, you can get 10 lines for employees very cheaply and set it up so it tries to reach all of them fairly easily. Voip.ms has a great wiki to help and also technical support that is helpful.
The only downside is that if you are someone who does not want to spend any time learning this stuff, and if you don’t benefit from a cost structure that is highly beneficial for keeping fixed costs low while having more flexible marginal costs, there may be more simple options out there. However, prior to going with voip.ms, I searched and searched. The combo of features and especially the price are hard to match. If you have zero technical experience and no willingness to learn anything (like the type of person who would struggle follow instructions to change something simple on a computer) it may not be the best for you, although they have a new softphone App that may make things easier.
I have had technical issues using voip.ms where I had to contact technical support to understand what was going wrong and it ended up being due to configuration issues. If you just use the App they created it’s probably much less likely to happen, and this happened to me before they had an App.