Choosing the best operating system

On Raspberry Pi 2, we have different operating systems :

Screenshot from http://www.raspberrypi.org/downloads/

• Raspbian is a valid candidate for our purpose, it's based on Debian, it has a GUI but can be launched without it (cool because we don't need it). Raspbian is the most used OS on Raspberry Pi so we can expect it to be the most stable.
• Snappy Ubuntu Core is in alpha version and we don't want an unstable computing farm so we won't keep this one.
• OpenELEC and Raspbmc are media centers so they don't fit in our project.
• Pidora, based on Fedora, could be valid but doesn't run on ARMV7 (Pidora is for ARMV6). A released version of Fedora seems to be the successor of Pidora because it's running on Raspberry Pi 2. For more informations, read this forum topic.
• Not in the list but still in competition, FreeBSD is a good candidate because it provides the minimum and it's preferred because we don't need much tools to make a computing farm. The only problem is that no version of FreeBSD has yet been released for Raspberry Pi 2, so we need to compile ourselves this version. Our project supervisor is actually working on that.

To conclude, for now we keep Raspbian, Fedora and FreeBSD as possible operating system for our computing farm, only the benchmarks will decide between these which one is the best operating system to achieve our objectives.