If you're application(s) aren't highly threaded and memory requirements fit within the 32GB memory limit of the iMac then the iMac is likely the better choice.With that out of the way IMO the general rule of thumb is as follows: I would highly recommend you avoid Geekbench scores and test with the applications you'll be using. Looking at Geek Bench, the iMac 2017 4.2 i7 and the 6-8 core Mac Pro 2013s are in roughly the same zone, both financially and power house wise. If it was half the price, then maybe, but it isn't. Although they can hold their own single and multi-core wise, the cost isn't cheaper and it doesn't have thunderbolt and could be unsupported at any point. The old cheesegraters don't stack up according to my research using geekbench. With laptops still being limited to 16gb ram, that leaves me with either getting an iMac or a Mac Pro. The sort of sessions I'm struggling to run are large orchestral VI sessions with lots of plugins which are being made on a 12 core 2013 Mac Pro with 64gb RAM if that helps anyone! However about 40% of my work is now at my home and I can work from there if needed in most situations. I do a lot of on-site work, so the laptop has always been the most helpful option.

I've held off upgrading for so long with the hopes that there would be a 32gb RAM Apple laptop out, but there isn't and my hand is being forced! I'm using a 2012 'classic' macbook pro, which has served me well, but I'm running out of power and can't open some VI heavy logic projects due to RAM shortage (and probably some cpu issues too).

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