I have been using this product for years now and it never disappoints me! The ability to connect many different types of devices (landline phones, VOIP phones etc.) It's easy to set up and configure and there are tons of options available from call recording to voicemails to IVR systems to custom softphones.
Some features aren't always intuitive but they're usually very helpful when we run into problems or need some help. We use the phone system at my work so having an all inclusive package was important.