Works fine here.
I have zfs root + refind on my laptop and grub2 + zfs root on my desktop with ssd cache drives. Works like a charm. It eats a bit of ram though
Just added a couple repositories to arch and build a new usb stick with zfs included.
The only backdraw is that I have to wait for the zfs repository to update whenever arch releases a new kernel. Usually it takes 1-2 days so it's not too bad.
Also, keep in mind that you can not offload the ZIL to another (ssd) drive for the root zpool so make sure you make a separate pool for the root and one with all the rest
You can add cache ssd drives to the root pool though.
Offloading ZIL (log) speeds up the writes and cache drives speeds up the reads.
Once you go zfs you don't go back as the possibilities are endless