Iris pro is very hard to justify both in terms of cost and suitability for purpose. About the only advantage it has is that it is extremely power efficient - making it useful for battery-powered devices and thermally-limited scenarios (such as fully-sealed, 100% dustproof PCs in industry) that still require GPU horsepower.
Honestly, I don't know what Iris Pro graphics are for outside of an ultrabook. Anything bigger in the laptop world and Optimus makes more sense - because if you need GPU power, you usually want more than Iris Pro can provide, and if you don't need GPU power then you're paying a high cost for something irrelevant.
When you take that expensive, relatively
low-performance IGP and waste its only trump cards by making an actively-cooled, mains-powered product it becomes nothing other than a platform demo. The people who will want one will want it irrationally for reasons like "it looks cool" or bragging rights, but it's definitely not a good product in terms of offering an advantage over alternatives, as the niche-of-niches that this appeals to must be minuscule."someone who needs a quad-core or a bandwidth-limited Thunderbolt 3 port in a small space, but still actively cooled and mains-powered"
Let's deconstruct that a bit:
- Needs a quad core - so someone who multitasks enough to require more than four threads, otherwise the 6300U also runs at 2.4GHz on all threads yet uses only 15W not 45W. Things I can think of that need more CPU compute power than that are high-framerate dGPU gaming (which rules out this NUC either via the IGP or via the messed-up PCIe lane configuration using an external GPU over Thunderbolt 3), compute for software rendering or compute for database analysis. Those last two typically benefit greatly by moving to non-mobile parts with even higher TDPs and core counts, making this NUC better than the 15W parts but far from the fastest option available.
- or a bandwidth-limited Thunderbolt 3 port - Well yeah, if you read reviews you'll see that the TB3 port on this is going to be starved for lanes. You could certainly get 'better than Iris Pro' out of a dGPU but it's barely worth it for such hassle and cost - and SIZE - making the entire form factor pointless! As for non-GPU options, uh - what was wrong with all the other miniPCs with the previous generation of Thunderbolt, again?
- in a small space - How small are we talking about that a faster Zbox E-series with a 65W 3.3-3.8GHz Broadwell is too thick at 51mm but the NUC is just fine at 28mm? Also, the NUC is longer at 211 vs 188mm so it's barely even a size win for the NUC.
- Actively cooled - Well that rules out most of the industrial niches like PoS units, billboards etc where cooling must be passive and anywhere dusty or volatile environment.
- Mains powered - okay, so there's no restriction on power draw other than TDP, and that's mostly constrained by size and how whiny you want the fan to be, so why not use a dGPU if you need more horsepower or desktop-class processor if you need more CPU compute?
What am I missing?