DON'T FORGET TO MAKE SURE YOU SCAN THE FILES ONLINE BEFORE YOU USE THEM.
Don't trust ANYBODY that's going to come around and say he has something that's too good to be true.
You can run a program in Sandboxie and have your AV watch it in there. If it tries to do something, your still 99% protected. (unless the program has an anti-sandboxie add-on, meaning it just won't run in sandboxie...)