Been thinking about this a bit, as I'm noodling over my own workstation refresh, with Black Friday looming (more on that later).
Last night, I was messing around and almost did a very bad thing. There was a 30% off sale, on the Dell Outlet, and I started to play. before I knew it, I had put an Alienware system with: 6-i7 3.8 cores, 512G SSD, 32G DDR4, 4TB 7200, NVIDIA 880 w/6GB DDR5, liquid-cooled, empty slots and drive-bays galore, etc, etc.... in my cart. It was a monster system, and way more than what I needed. With the Outlet coupon, combined with normal outlet discount, the thing added up to just shy of $2,000, including tax.
Bit alas, i'm an adult with kids to feed and a mortgage, so I figured I'd sleep on it. Woke up this morning and that unit was no longer available, and the 30% off sale was over. Duuuuh! Wondering if not buying it was a good or bad thing?
But the more salient point is, I now find myself seriously considering a Windows workstation again. While the pro in me could certainly make do with an iMac or MacBook Pro, the Power User in me is wanting more. Five years of iMacs have been OK, but I'm getting over the whole rip and replace thing, and it's really bugging me that they're so hard to do maintenance on - with even the small stuff being a PITA to fix. For example, the stand just broke on my late 2012 iMac (it now flops down, if I don't wedge something underneath it to prop the screen up). Even though it's still covered under AppleCare (expiring in a couple months), fixing that would cost ~$400-500 if it wasn't covered. And getting it fixed will likely mean at least a week, without my main system. For a $1 plastic part that snapped in the stand.
With a PC Tower, a broken component usually represents a component upgrade opportunity - with an iMac, a broken component is an inflection point (trash it, or spend more than 50% of what it's worth to make it work exactly as it did before).
I totally get how the current Mac Pro is appealing to Creative professionals that need lots of horsepower. I'm sure you pros already have big external RAID arrays and such floating around anyhow, so external connectivity is a good way to go. And your company is probably OK with just refreshing every couple years, as they do with laptops already. So, that approach makes perfect sense. But for a simple Power User, like me, I just find myself wanting more upgradeability and options.
Biggest reason I resisted leaving Apple, up to and including moving from earlier Mac Pro to iMacs, was the Apple ecosystem. But now that Apple is pretty much strong-arming me into putting much of that into iCloud anyhow, that's no longer such a big issue. (I literally just received my monthly iCloud bill, as I was typing this... LOL).
Still kind of wishing I had bought that discounted system... LOL