I stayed here before last Christmas with my girlfriend for a few couple of days and I think it is a beautiful property with beautiful rooms like in movies, I think it is an old coffee farm and they have really preserved the vibe. I just returned to Flyertalk after some time so wanted to leave my experiences here. Watch the music video of "Beautiful" by Snoop Dogg and Pharrell Williams and it will look like that. Breakfast is also really great, while not the largest selection the quality is top notch.
The one thing that bothered me personally though is the violence in the area. We never experienced anything physical ourselves, but one night we heard a few gun shots right below us on the street (we were sitting in the bar of the hotel at night and the barkeeper waved at us to move away from the balcony) and at night you hear heavy gunshots from the favela close by to the West. We did walk back from the famous stairs (Escadaria Selaron) and met one of the hotel concierges on the way - otherwise, it was a deserted walk at day time like 3pm and right below the street the favela starts. Not sure what I was thinking and I would not do the walk again - we were really asking to get robbed, but somehow nobody approached us on the way, so we got lucky.
Having said that, all of this was about a year ago, maybe the situation has improved by now. Taking Uber in and out was safe and if you stay at the hotel it really is a beautiful property. As a plus, you can use the beach of the other Sofitel down in Leblon area, they will provide you with towels etc. if you tell them that you are coming from the other Sofitel in Santa Tereza.