The Mercure Grand Ibirapuera was recommended to me by a colleague. Convenient for business (my purpose), less convenient for tourism.
I was extremely impressed. I travel frequently on business world-wide, and I would definitely rate it higher than all hotels of its class (and rates) in Europe and many in North America. Modern, spacious, attractive rooms. Free high-speed access (with my corporate rate). Well-appointed, ergonomic bathrooms. Simply excellent room service, the kitchen does very well.
But the best part was the service. The entire staff, no exceptions, genuinely make you feel welcome and sincerely strive to help and make your stay better. As someone who travels all the time, I very rarely come across this. This was without a doubt 5-star service at a place that charges much less. This hotel is an exceptional value, I'd strongly recommend it and would gladly come back.