I am able to make calls from any place in the world, even if my cell or landline service are not working (such as emergency situations). Some of its functions may seem complicated at first but they're very user friendly once you get used too them. It's great how it automatically updates itself with new software versions so there are no problems when updating your apps. You can only use one account per computer/phone line; otherwise all clients would receive messages through another client which could be confusing sometimes. If you like making international conference calls this product has got nothing wrong in comparison to other products available out there. This makes managing large conferences much easier! We have been using PABx since we started our company almost ten years ago now. The benefit over traditional systems was immediate - call quality, ability to use multiple lines simultaneously without confusion.