Basically I had a 6 core Mac Pro 2013 with D700, 64GB RAM etc. Found myself using it less and less since working away from the home office a lot so I picked up a maxed out rMBP 2015 for use on the road. The new rMBP was fast enough and I felt I didn't need the MP and promptly sold it. Now that I'm working from home more, I find myself missing the MP. Things like Mission Control stuttering, running a couple of Virtual Machines, and occasional Handbrake batches and gaming have me not quite pushing the limits of the rMBP but certainly missing the quiet and of course the convenience of a powerful desktop and notebook combo. The rMBP also lags like crazy with a single 4K display - like almost unusable sometimes (didn't have a 4K display with the MP so can't comment if it had the same issue). I'm looking to get a desktop again, but can't seem to decide between the iMac 5K and the MP. The new iMac appears to surpass the quad core Mac Pro and almost touch the 6 core Mac Pro for most things. Gaming wise it can't compete against a pair of D700s in crossfire but as a single GPU a 295X seems slightly faster than a single D700. However...it's only very slightly faster than the rMBP I have (like 15% in Geekbench, although graphics is quite a bit faster). Which basically means the only viable Mac Pro to give me a substantial bump above an iMac would be an 8 or 12 core. Has anyone any experience with the iMac 5K doing things like gaming, batching video compression or running VMs? Any stuttering on the user interface? Any noise or heat issues? Any stability issues with the iMac (since it doesn't use ECC RAM and the Mac Pro does)?