I like that it can be used by multiple people in different offices with ease, as well there are so many features to choose from for each person working here! There aren't any downsides at this point - everything works perfectly fine when using our own network (the office).
It's easy enough if you've ever worked within an organisation before but not really difficult either. The cost of getting set up initially was quite high due mainly because we had never dealt directly withe business telephony prior or been able t work through anything other than VOIP providers such as Cloudflare etc., however after contacting them they were very helpful & friendly throughout all stages which made things easier once completed.