Hello!
I am using BTRFS with Bananian and Armbian. (3 Banana Pies: 4x external USB hard drives, 1x SATA SSD… everything with BTRFS)
Armbian with an external SSD (SATA):
root@bananatest:~# uname -a
Linux bananatest 4.3.3-sunxi #3 SMP Mon Dec 28 11:27:16 CET 2015 armv7l GNU/Linux
root@bananatest:~# dpkg -l | grep btrfs
ii btrfs-progs 4.2-1 armhf Package created with checkinstall 1.6.2
root@bananatest:~# btrfs --version
btrfs-progs v4.2
root@bananatest:~# mount | grep btrfs
/dev/sda1 on /mnt/BTRFS_POOL_SSD type btrfs (rw,relatime,ssd,space_cache,subvolid=5,subvol=/)
/dev/sda1 on /mnt/Data type btrfs (rw,relatime,ssd,space_cache,subvolid=257,subvol=/@Data)
root@bananatest:~# cat /sys/block/sda/queue/rotational
0
I am still using btrfs-progs 4.2 (self-compiled). It's working good (compression: lzo and zlib, subvolumes, snapshots, scrub, checksums). If you want to use compression, you should use lzo.
With BTRFS I was able to detect a buggy USB hard drive controller.