I have a valid 10 year visa and arrived back in Brazil this morning. The AAgent who checked me in last night didn't even look for a visa. The Brazilian borders agent scanned the front page of my passport and asked me how long I will be staying, he tried to put an authorization through a computer system but it bounced. I then directed him to the visa which he keyed in manually and that worked, he gave me the usual CLAS 1 DOC 3 stamp. It took about 4 minutes vs the 30 seconds most of the Brazilian passport holders were taking.