Arrived early.  Spotless, loaded with Big Sur.  I could have convinced someone I just walked out of an Apple Store with it new (in 2015 : ).  Very happy with it, and surprised, judging from some of the bad reviews I've read here.  I've had some sudden and mystifying data disappearances once I migrated stuff and started using it, but I suspect that more about Big Sur running on an older device, and haven't figured it out yet.  Will update review if my contentment changes.