MinGW: A native Windows port of the GNU Compiler Collection (GCC), with freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All of MinGW's software will execute on the 64bit Windows platforms.
Installer is crashing quite often. There is some potential in development, but stability of like pre-alpha product.
The MinGW project doesn't seem to be well maintained. At the time of writing (2015), the package manager only seems to only have about 6 packages and all of them are from 2013. At this point in time, it is generally better to use MSYS2. Also, I agree that the installer is bad. The UI for the installer is trying to incorporate checkboxes and radio buttons into some big sentence/paragraph, which is weird. A good UI should try as much as possible to stick to elements that people are familiar with and understand. (If you are MinGW developer, this is not intended as a personal jab at you. You have no obligation to maintain this project and you don't owe the community anything. The work you did on this project was useful.)