I do quite a lot of photo and video work (privately, not professionally), and up to now been happily working on my rMBP and cMBP before that. However, now that I am going to be doing more video work compared to previously most of just still photos, I am starting to feel the limits of my 2012 rMBP. However, the choices within the Apple system are a bit limited and combined with the prices, I was thinking about building my own Windows PC again. Basically Mac Pro power for Macbook Air prices, but without OS X. You know how it works. Then again, I really like working on OS X. Then I was thinking I could get a second hand 12 core Mac Pro 5.1 for reasonable money, fill it up with memory, add some storage, PCIe M.2 flash storage, possible upgrade the CPU's and video card and I could possibly end up having a pretty hefty beast of a machine for the price of a new 27" iMac. Since I don't need the screen of the iMac as I prefer to work on my Cintiq, and a new Mac Pro is way too expensive for what I do this might be the ticket. Am I crazy thinking along these lines and should I leave the old Mac Pro's where they belong, in the past? Or is this indeed a valid strategy to get a reasonably priced powerhouse that can last me another 4-5 years?