After two macbooks were ordered and delivered, I thought this was it. Finally I found an inexpensive replacement for my 2015 MBA.I’ll start with the positive.  It worked great until the update.  Also I come to find out the computer isn’t upgradable anymore, the Mac gets hot and runs its fan whenever there are two or more programs running. Plus it is glitchy and the rubber gasket around the screen is falling out.$499 for this?  I think I learned my lesson.  Buy it new, or don’t buy it from Amazon.