This device is interesting for what it is, but ultimately it's just mid-tier gaming laptop hardware fitted inside a compact case. Just like a laptop, the potential for future upgrades is going to be limited, but unlike a laptop, it lacks an integrated screen, battery or input devices, so it can't be used on it own. It always needs to be tethered to an external display, keyboard and pointing device, and plugged into an outlet when in use. The portability loses a lot of its value when the device is designed to primarily sit in one place and not get moved.
And compared to gaming laptops, this Mini PC is quite expensive for the hardware you get. It's around $1400, while better equipped laptops can be found for hundreds of dollars less. Just a brief search turns up an MSI laptop at Newegg for $1150 ($1050 after rebate), with the same CPU and the same amount of RAM, but with a 6GB 1060 and a much more usable 512GB SSD. Plus, you get an integrated 15.6" display, SteelSeries backlit keyboard, trackpad, speakers, DVD burner, webcam, and a battery, allowing the device to be used anywhere. Sure, it will take up a bit more desk space, although once you add a keyboard to the Shuttle X1, any size advantage it has will be negated.
I suppose it could fit a little better into a home theater environment though, where it's going to stay connected to a television and be used with wireless peripherals. Unless you are completely starved for space though, you could undoubtedly get more performance with desktop hardware for less.