I search for yunohost users using banana pi R1, to know if it works well. But I suggest to speak here of different kinds of arm boards.
Personnaly I used the famous Olinuxino Lime 1 (Internetcube/brique internet).
And you ?
I use Lime2 (Gigabit Ethernet, and, more important for my Duniter node, moar RAM !) with a 3.5" WD RED hard drive (for my NextCloud files and for future cross-backups with a friend’s InternetCube, some day…)
Regarding the Banana Pi R1, I have read a lot of bad things… A good synthesis is available in the Armbian issue to drop R1 support.
Otherwise, I own a Banana Pi M1+, which works great, but I’ve switched to a NAS with Virtualization for my self-hosting needs for CPU and disk (space+RAID1) reasons.
My yunohost server run (inside docker) on a classic Raspberry PI 3 (Raspbian).