We had a great time in Copacabana. The studio has a great location, 5min walk to the beach, big 24/7 supermarket and just right in front of the bus stop (buses to centre, Christus, airport...). Travel agency, exchange money & bank are next door. The apartment has an equipped kitchen. Terrace is a great breakfast spot :-) (with the view on Christus).
The only disadvantage is a noise at night. Since it's on a main street it gets really loud when you open a window.
In general I highly recommend it for travelers who want to have an easy access to all Rio's highlights & enjoy Copa!