The location is definitely great if you want to be close to the beach and the clubs, neither of which are good in Barcelona. The location is not great if you want to avoid getting robbed. Before COVID this area used to be dangerous after dark, now it's even worse. (And by worse I mean that someone literally stabbed out the tires of my car as I was driving, in order to steal our passports from the back seat, the police says this is super common post-COVID. Didn't happen right next to Arts, but speaks to the overall situation in the city.)
The location also sucks if you want to enjoy the things Barcelona truly excels at, here you won't be surrounded by amazing restaurants or beautiful architecture. Almost every lunch or dinner will involve a decent amount of driving.
I lived in Barcelona for around 4 years pre-COVID, so this isn't just a panicky tourist take. The area attracts robbers because it's relatively secluded but draws in a lot of drunk wealthy foreigners, going in and out of the Arts, Casino and Clubs. I wouldn't walk around here wearing any kind of a watch.
EDITION and Cotton House are the Marriott properties I hear good things about.
The EDITION is very good - I stayed there twice last summer. I also quite liked the W last summer - if you want to be near the beach, the W location is better than the Arts IMO. I walked extensively around that area as we are big walkers. Arts is very close to the kind of clubs I would pay to avoid, but then I’m not a big fan of nightclubs or the kind of clientele these particular venues seemed to attract.
Unless you specifically like the beach or want to go clubbing/gambling, the location of the EDITION is vastly superior for a city break and sampling the more authentic and desirable parts of Barcelona.