I moved from Mint XFCE to Xubuntu and in the 15.04 release everything works out the box as well, even the monitor setup with the open source radeon drivers via xfce4-display-settings -m is one of the best I've used for 3 screens with one rotated.
Absolutely painless all around and XFCE 4.12 is a nice little upgrade just gentle improvement all around but functionally the same.
With Mint, everything works straight out of the box - except for dual monitors, which was a cinch to set up. Great distro.