You've pretty much answered your own questions... The 125AAs are lighter but not as stiff as the 125s... The 125s are very shiny and the 125AAs are anodised, so less shiny... I'd go with the Cro-Mo B125, I don't really see the point of the 125AA as I've heard a few complaints about them being too flexy for the track... Your call really... :]
You've pretty much answered your own questions... The 125AAs are lighter but not as stiff as the 125s... The 125s are very shiny and the 125AAs are anodised, so less shiny... I'd go with the Cro-Mo B125, I don't really see the point of the 125AA as I've heard a few complaints about them being too flexy for the track... Your call really... :]