I have a 2009 iMac (3.06 GHz, 8GB, Nvidia GT130, 1TB HD) which runs fine for my current needs. I use this as my main work machine, with Archicad as the most demanding ap. I was planning on purchasing a new 27" iMac, but what about simply upgrading the HD to a 256GB SSD, and maybe upping the ram to 16GB? The new 27" screen is the biggest draw for me, although I find the size and resolution of my 24" to be fine (and in way preferred to the higher resolution of the 27" which makes me squint). No doubt the 27" resolution is a matter of getting used to (or upping my glasses prescription). Cost of upgrading my 24" iMac is about $500 at a service shop versus $2500 for a new machine. Thoughts anyone?