There is a Synology release which works on rPI2 without a chroot. However it's seems to becapable of playing media that the drobo/chroot version was unable to. If you want to try it:
See the guides here: https://forums.plex.tv/topic/145717-i-have-pms-running-on-raspberry-pi-2/?p=887965
and here: http://www.htpcguides.com/install-plex-media-server-on-raspberry-pi-2/
There's also a conversion guide for moving from the chroot version to the native version here:
https://forums.plex.tv/topic/145717-i-have-pms-running-on-raspberry-pi-2/page-17#entry886641
UPDATED Image using the ARMv7 install: http://www.mediafire.com/download/dred4bd078wwe9n/MiniBianPlexArmv7.zip
And it was surprisingly easy!
I followed the bitbucket guide for installing the drobo PMS into a debootstrap chroot on raspbian.
As described here:
https://bitbucket.org/inkubux/cubox-i/wiki/Plex%20Wheezy
As with the Mycloud install, I had to change LC_ALL=C in the chroot plexmediaserver script and install libexpat1 (apt-get install libexpat1) in the chroot.
I'm using a WD MyBook to store my media. So once I had PMS running I created media folders in the chroot and then mounted the mybook folders in the main host. So my main host /etc/fstab looks like this:
# Chroot bind mounts /home /chroots/wheezy-armel/home none bind 0 0 /mnt /chroots/wheezy-armel/mnt none bind 0 0 /tmp /chroots/wheezy-armel/tmp none bind 0 0 /proc /chroots/wheezy-armel/proc proc defaults 0 0 /dev /chroots/wheezy-armel/dev none bind 0 0 /dev/pts /chroots/wheezy-armel/dev/pts none bind 0 0 /mnt/USB_HD/Video/Films /chroots/wheezy-armel/media/films none bind 0 0 /mnt/USB_HD/Video/3D_Film /chroots/wheezy-armel/media/3dfilms none bin d 0 0 /mnt/USB_HD/Video/TVShows /chroots/wheezy-armel/media/tv none bind 0 0
Then I just add the chroot version (e.g. /media/tv) from the Plex GUI.