As promised, I'm reporting back my test results with Fedora 21 (64bit MATE Spin).
The installation to a clean drive is about as simple as it gets. Enter your language, select the disk, enter your username and password and that's it. Takes about 10 minutes to complete and I was up and running with MATE 1.8.1. It did take several more hours to tweak the UI to my taste and install all the software, such as GIMP, Libreoffice, VLC, Mythtv and so on. I then transferred all of my personal/user data to the new install.
I use two 320GB drives for my Fedora installs and one 2TB drive for data storage only. I alternate Fedora releases on the two 320GB drives. In this instance, I replaced my older Fedora 18 with Fedora 21, while keeping Fedora 20 active on the other 320GB drive. For me, this is the best approach and allows me to not have all my eggs in one basket.

While Fedora 21 looks pretty much like earlier versions of Fedora, it has a more polished feel to it. So far, I haven't ran into any odd quirks or bugs with MATE. Everything just works, which is what I expect from a top notch Linux distribution. My overall rating for the release of Fedora 21 is 5 out of 5 stars.
