I stayed three nights at Brunello's place. Very convenient and very well decorated. Brunello was very open and available every time I needed information before my stay in RIO.
His appartment (I wouldn't say loft) is small but very well organized and clean and above all at the very heart of IPANEMA. It's a bit noisy but very safe. I would just suggest a larger bed... Anyway, very nice place to stay in and very close to the beach !