@Andrew,
I have my 24 inch all-in-one PC in a modern bureau desk in my living room. This new Zotac seem perfect as a replacement.

I dont want a huge floorstanding PC, but a hidden, silent and efficient one. I can fit an Acer 27" in the desk in front of this. A laptop is to small.

You have space in your adolescent room -> classic gamer PC
You need a hidden/small but efficient living room set up -> Zotac EN1070

You need to have a look at the tray price.
6300HQ is more expensive because it can operate at a higher clock rate with higher TDP while still at a considerably low TDP.

Why wouldn't they just build it with the freaking i5-6300HQ instead of the 6400T? The 6300HQ draws the same power on average even under full load (the 6300HQ is a 45w CPU but that's also counting for the 10w iGPU included, so it's comparable to a 35w model in any case) AND it runs cooler than anything else out there save for ULV chips.

Oh did I mention it's got a higher base AND boost clockspeed than the 6400T?

6400T = 2.2GHz to 2.8GHz maximum boost.

6300HQ = 2.3GHz to 3.2GHz maximum boost.

Yes it's only a single core boost for the max, but the full chip can do 2.8GHz across the whole CPU at 100% load. It's just... silly to buy this for any reason. You get essentially the guts of a 15" laptop... and have to supply your own monitor and otherwise. Boggles my mind when I see this kind of thing. xD