There are currently lots of role player SF's in the league who can defend, shoot the 3, and maybe do a little bit of scoring. Guys like Batum, Ariza, Pietrus (a few years ago), Grant Hill a couple years ago, Luol Deng, Shane Battier, etc. types. I think Jeff Green is right now in that class and has the potential to be the best in that class, but always will be below the better SFs who can do more like Iguodala, Granger, Pierce, Rudy Gay, etc.