Just to remind -- check Release notes for version you want to install, if all APs you have, are supported.
If you have only 802.11ac APs, you are safe to use any new version you like. I would recommend trying the latest, if you don't have any issues, use it. If you get any problem than use recommended older version.
You can't upgrade directly from 10.1 to 10.5, but this is described in Release note section.
