Luther was a beast live AND in studio. His voice was distinct. I think that's the problem. There aren't many distinct voices out there. Jason DeRulo, Taio Cruz and Mike Posner are way to similar for my liking. As for real R&B male, Usher (though he can blow at times), Ne-Yo, Chris and Trey Songz are all cool, but I need something like this on radio constantly playing:
Who says something like that!? 
This Bitch