Location is great - just what we needed for travelling into and out of Sants station. The check in was really slow - long lines, and even though I did the online check-in, the person didn't seem to know how to use it. I still got asked for my ID, and it didn't save any time.
The rooms were modern, clean, and comfortable, except I don't like rainfall showers - it's really impractical for keeping your hair dry, and the normal shower was at belly-button height, which isn't practical at all. Also, the walls are super thin and we could hear the neighbors walking around, packing, showering, etc.
On the sustainability side, there are glasses rather than disposable cups in the room; and the shampoo, conditioner, hand soap, and moisturizer is in big bottles rather than tiny single-use ones, which is great! However, there were still disposable coasters under the glasses (why not switch to reusable ones if you insist on having them - it would be fine without!). And there were overpackaged toothbrushes, shaving kits, vanity kits in the bathroom - why not go for less packaging, and offer them at reception for people who really need them, rather than to everyone.
Finally, there were way too many pillows on the bed, and the decor is way over the top - a lot of embodied carbon - all using up a lot of resources to produce and wash/maintain. If you want to to be more sustainable in the future, all this could be scaled back a little, rather than replaced next time there is a refresh.