If you ever test out pure Debian, you will love Iceweasel. Yes, I know Iceweasel and Firefox are the same thing, but Iceweasel has a few tweaks by the Debian folks. I had hoped Iceweasel would be the default in LMDE, but I can understand the Firefox decision. At least it was an easy install for you.
Currently running in the computer lab:
Linux Mint 17.2 Cinnamon
CentOS 7 GNOME
Debian 8 LXDE