Finished the demo an hour ago. It's not that bad, actually, but at the same time it's nothing special either.
I enjoyed the atmosphere, the visual presentation and the music. Battling in destroyed cities with giant mechs against robot tanks, flying drones and (of course) other mechs is pretty intense and felt satisfying once I figured out how to play the game properly. The underlying story seems quite generic so far but I am quite sure it will have a plot twist or two around the corner, so yeah it got me a little interested.
The controls are not that easy to learn, unfortunately. It took me quite a while to manouver the Arsenal efficiently and smoothly, but once I got that figured out the gameplay became much faster and even more intense. That was a nice feeling. I also found a hidden treasure by scanning a building, so maybe other missions will feature more secrets. I would appreciate that.
The boss fight was tough, and I liked it! I dieded once but managed to kill it in the second try. The boss punishes you for just rushing on him and shooting his weak spots, so a little strategy is necessary. I can imagine that later bosses will also rely on careful approaches.
The only thing that really bothered me was that sometimes enemies can be hard to spot unless I stare at the mini map, and I tend to avoid controlling my mech through the mini map alone. I wish they could stick out a bit more against their surroundings. That would be great. Also, I haven't figured out why I ever should leave the Arsenal and walk around as a little whimp. Maybe there are some uses for this, I don't know.
Altogether this is basically the doll fights from Xenoblade Chronicles X made as a new game. That's okay for those who like these things.