One last advice request for you guys. This is a used buy I'm keeping an eye on. Would you recommend this system for 4k editing with fcx? If I have to buy a brand new maxed out imac I will, but I'm doing my best to be frugal and find a used system that will work. Potentially cutting a 4k feature on whatever I purchase.
"Great condition Apple iMac 27", late 2013 model. 3.5Ghz Intel Core i7 Quad processor, 16GB 1600MHz DDR3 RAM, NVIDIA GeForce GTX 780M 4GB GDDR5 graphics, and 256GB SSD storage."
I'd definitely max the RAM out to 32gb and use external hard drive for footage.
Thanks for any thoughts!
That is a very good machine -- I used one for two years until I got my 2015 iMac 27. It doesn't have the Retina screen which ironically makes more difference on text than graphics. Before I redeployed it to another editor, I did a bunch of tests on it vs the 2015. It is not that much slower: https://photos.smugmug.com/photos/i-3mL6T5r/0/O/i-3mL6T5r.jpg
IMO for comfortable H264 4k editing you ideally need faster machine than a top-spec 2015 iMac 27, even considering the performance advantages of FCPX. However I edit 4k every day on mine and it's usable. For this reason I don't see the benefit of "stretching" your purchase and getting a 2015 machine. If you need a machine now it's better to wait and see what the new machines look like since they will likely have a substantially upgraded GPU.
Whether 2013 or 2015 iMac you have to transcode 4k to proxy much of the time for best performance. So in that sense there is even less difference between the 2013 and 2015. I love the Retina screen but the non-Retina 2013 was a good machine.