WinToUSB's key features include
Easy-to-use wizard interface that provides step-by-step instructions for creating a Windows To Go USB drive.
Creation of Windows To Go from an ISO image file or CD/DVD drive.
Clone an existing Windows OS (Windows 7 or later) to a USB Drive as a Windows To Go Workspace.
Use of a Non-Enterprise Edition of Windows 10/8.1/8/7 to create Windows To Go Workspace.
Creation of Windows To Go on Non
Certified Windows To Go USB Drive.

Extra features of the Enterprise Edition
Clone current Windows OS (Enterprise edition of Windows 10/8.1/8/7) to a USB drive as a Windows To Go Workspace
Clone current Windows OS which on a dynamic disk to a USB drive as a Windows To Go Workspace
Clone current Windows OS which on a USB disk (Windows To Go USB drive) to other USB drives as a Windows To Go Workspace

Important notes
Windows 7 is not completely portable. You may have driver problems when booting on different computers, so highly recommend using Windows 10/8.1/8 to create portable Windows.
Windows 7 does not have built in USB 3.0 support, so Windows 7 will have to be booted from a USB 2.0 port.
The common USB flash drives are very slow. It takes a long time to install and run Windows from a common USB flash drive, highly recommend using a USB hard disk, a Windows To Go Certified Drives or a SanDisk Extreme CZ80 USB 3.0 Flash Drive to create portable Windows.
Windows To Go drives can be booted on different computers, so you can carry it to anywhere and use it on any computer.
You need to be an administrator on the computer you are installing the WinToUSB on.

Whats New :
Add support for Windows Server 2016 Technical Preview
Fixed bug: Failed to convert internal hard drive to Windows To Go drive
Fixed bug: Failed to create Windows To Go from a VHD/VHDX file
Fixed bug: Failed to format USB flash drive