I have a regular old masters in CS from GT. It's probably worth it from a career standpoint (if nothing else it signals that you care about self-improvement and take active steps to doing it). I would expect you'd miss some of the 'grad school experience' (for better or worse) and networking opportunities. The actual content itself can probably be gotten for free from other courses on the web if you take a syllabus from a CS dept to get an overall program. That path wouldn't have the benefit of access to teachers and would require a lot of discipline.

I don't know how it would be looked at in Brazil or what the economic cost/benefit are in terms of your own income. I did know a few folks from the University of Sao Paulo that did grad and postdoc work while I was at GT though, so clearly some people are aware of GT in Brazil. That might be another avenue to get opinions from. I would be interested to hear how the costs compare to an institution that was local to you.