My stay at Casa Sagnier was exceptional. The hotel is perfectly located in Eixample, and very accessible to everything I needed and wanted to do during my stay (from tourist sites to train stations). The staff were friendly and inviting, and highly attentive. If you like, they offer a live chat with the front desk for anything you may need via their WhatsApp (everything from restaurant bookings and recommendations to room turn down services). The room was plenty spacious for me as a single traveler, and even if I had a partner there was still plenty of room to pack away my things (I travel with two large suitcases).
I had lunch and drinks one day during my stay, and the food I got was incredible and the drinks delicious. The service style is very lax, which I was not used to at first as an American, but you learn to take your time and enjoy your time in the atmosphere.
Overall, it was a very pleasant stay. I would definitely be returning on my next trip to Barcelona.