I've got a mid 2011 27" iMac that is still zipping along nicely - since I do just about everything on my laptop other than work requiring a large monitor. It has 8GB RAM 1333 MHz DDR 3 and a 3.4 GHz i7 Intel processor ADM Radeon HD Graphics Card, and dual hard drives, a 251GB Intel 6 SSD and an Intel 6 1TB HDD. That SDD was pricey at the time but best decision I ever made. Anyway, I'm thinking of upgrading to a 24MP camera so much larger RAW files and wondering if I should get two more 4GB RAM cards (or whatever they are called) to fill in the two empty slots and upgrade it to the max 16GB RA