I think it is something fundamentally wrong when a rapper has to rap over his own pre-recorded vocals on live shows. TV shows with one or two songs are one thing but I think it's something that should be avoided at whole concerts. A rapper should be able to perform his lyrics without having to rely on a voice in the background. It's a sign of weakness (or a need to go back to the gym), no matter what your name is and who you are. Unfortunately most rappers are doing just that nowadays but it annoys me at concerts or concert DVDs when I notice that recorded voice in the back. Big ups to rappers able to rap without pre-recorded help.