The ability to manage multiple calls without having to jump back into each call, being able to have all of my contacts in one place for quick access when needed, I can easily refer them with just 1 click! Sometimes it takes time before they are updated but other than this no issues so far.
It's easy to use as well which makes things easier. Nothing at moment though maybe more features could be added like creating your own scripts or something similar? We're using VoicEmp internally within our organization where we handle many customer service related tasks (customer care).