I'm running 10.12.6 on my MacPro 12 Core (Mid 2010) with 64GB and 520GB SSD Drive plus QTY 3 x 3TB Internal HDD Drives.... plus 15TB DroboS Gen 2 (Firewire). I want to upgrade to High Sierra... all my core software has been updated to be compatible... anyone have any issues with upgrading an old MacPro 2010. Inhave a full backup on my Drobo of my entire system (520GB Boot Drive plus QTY 3 x 3TB Internal HDD Drives).... so I feel safe enough... but always nervous about upgrading, especially as my machine gets old and older. Should I be concerned about this APFS feature...? I upgrade my new MacPro 2017 with Touch Bar and had no issues at all.... but I have nothing important on that computer so I wasn't too worried if anything happened on there...but this is my main work machine... a very different story with this computer. Any comments or suggestions most welcome.