The converted raspbian image (offered here) does not expand /data partition on first boot as expected.
It is suspected that affects all raspberry3 conversions.
In a 32 GB SD card, disk usage after first boot:
pi@raspberrypi:~$ df -h Filesystem Size Used Avail Use% Mounted on /dev/root 3.4G 1.3G 2.0G 39% / devtmpfs 459M 0 459M 0% /dev tmpfs 464M 0 464M 0% /dev/shm tmpfs 464M 6.2M 457M 2% /run tmpfs 5.0M 4.0K 5.0M 1% /run/lock tmpfs 464M 0 464M 0% /sys/fs/cgroup /dev/mmcblk0p1 253M 48M 205M 19% /uboot /dev/mmcblk0p4 120M 1.6M 110M 2% /data