I have a 2014 2.6 GHz/8GB/1 TB SSHD. The UI is painfully slow - an old Mac Pro leaves it for dead. The drive is a Seagate 1 TB SSHD, with 8 GB of flash, and is brand new. I've done a clean install of Sierra, allowed it to index for days, and I still get the rainbow beachball. Does the 2014 really suck that badly? I have a 2012 2.3 i7 that is MUCH more responsive, with no beachballing (also has 8 GB RAM and a 1 TB 5400 RPM drive).