The Arts really isn't located near anything. It sits out near Diagonal Mar shopping center, fairly close to the sea in a little tourist enclave that could easily be Cleveland if not for the pictures of Paella in front of every restaurant. Tacky discos filled with drunk Brits, etc. I'm not a fan if you can't tell.
The hotel itself is nice; while I have not stayed there I have eaten in the restaurants a few times and wandered around the property a bit. The comment I made on my first visit is still accurate from my point of view: if a drug dealer from the 1980's were to design a hotel, this would be his idea of "really nice".
I'm not trying to scare anyone off and I'm sure others here have a lot more experience than I do with this type of property. It seems to me that with well-situated, unique places like the Om, Silken Diagonal, and Florida, there might be better choices to make, though.