With the official Fedora 21 release due out soon and the release candidate being available this weekend, I ran some basic performance benchmarks comparing the speed of Fedora 21 64-bit to that of Ubuntu 14.10 on an Intel Xeon workstation.
Fedora 21 Workstation was compared to Ubuntu 14.10 using the x86_64 version of each and maintaining the default settings. Fedora 21 is shipping with the Linux 3.17 kernel, GNOME Shell 3.14.2, X.Org Server 1.16.2, Mesa 10.3.3, and GCC 4.9.2. The package versions this time around aren't too far off from the Ubuntu 14.10 Utopic Unicorn release from back in November with the main change being the use of the Linux 3.16 kernel.
Ubuntu 14.10 Utopic Unicorn with the MATE desktop environment is a very cool distro. It suffers from two big problems, one of which has been inherited from its Unity parent, and that would be the inability to format old partitions, created by previous versions of Ubuntu. This is somewhat worrying. Samba printing is another disappointment. There was no screenshot problem like with some other distros, though.
Besides these issues, everything else was perfect. Familiar, friendly, extremely productive. Super fast and super stable, too. There was nothing out of ordinary, no problems. Suspend and resume worked without any issues, the system blazed at the speed of light, and with maybe ten minutes of work, you can transform it into anything you want. Docks, menus, new fonts, new themes, all there, just waiting for you. Total freedom and fun.
There can't be a perfect score, because the associated problems do not allow it. But assuming you had this distro given to you, and someone bothered to install the needed Samba package that normal people require, it would be an excellent alternative to many other mainstream releases. Highly polished, slick, and almost overwhelmingly simple and easy to use. The grade is something like 9.0/10, but it can do better. I demand it. For you, this is an excellent test bed. Go for it.