In August of 2017, I bought a new bottom-of-the-line 27" iMac (5120x2880 pixel retina display), with fusion drive upgraded to 2TB (128GB SSD cache), a 4TB USB C backup drive, and an extra 16 gigs of RAM, compliments of Crucial (total: 24GB). This page contains images of its specs.
The machine is named "Gabriel". I like to name my Macs after archangels.
Click on either image to see the full-scale version.