so the Sierra download I made last week was corrupted. it was obvious at first since I was able to create a USB installer and the USB stick boots fine. except that I was having issues proceeding in MacOS installation that after an hour of playing around, I got a message that says my USB installer was corrupt. I downloaded it again and now it's working fine. When downloading Linux ISOs, most (perhaps all) distributions provided an MD5/SHA1 code so I can check my downloaded copy with those. So is there way to check for the completeness of Mac AppStore downloads? I'm not so concern with small downloads but very concern with 1+GB ones. Thank you.