I feel safe and go down alone most of the time. While it CAN be dangerous, and there’s no guarantee you’ll be 100%, so can anyplace else in the world if you’re not using common sense or not being aware of what’s going on around you. Basically, don’t go into high crime areas or places you’re not supposed to go. If alone, try not to get too drunk and act the fool, or trying to be Mr. Big Shot, flashing $ and jewels (I’ve seen idiots doin it before). I personally think you’ll really enjoy Rio, someplace that should be on every mongers list!