with a rasberrypi you have to run a pruned node, or connect an hard disk via usb2(there is no usb3)
with a bananapi you have a sata port so you can connect the hard disk directly. So with a bananapi you can run a full not pruned node. Everything else is almost equal.

I don't like pruned node because, if for some reason I have to perform a rescan I have to download the entire blockchain another time.

Also Im not sure if pruned node relays blocks.