Zenmap is the official Nmap Security Scanner GUI. It is a multi-platform (Linux, Windows, Mac OS X, BSD, etc.) free and open source application which aims to make Nmap easy for beginners to use while providing advanced features for experienced Nmap users.
The best thing about this software it's that you can scan computers from anywhere in your network without having physical access or even being connected with those devices! I also like how fast my scans are when using zen map compared other softwares out there such as nessus/napititecnsis(sp?).
There isn't anything i dislike really but if possible try getting more people working together so we all have better results at once since its slow sometimes due too many scanners running…
Pros
It's very fast and easy to use! It has a lot of options to choose from and it makes scanning devices easy and fast