I have seen them both live. Christina's Back to Basics Tour was one of the best concerts I have ever attended. Such an experience. Britney's Femme Fatale Tour was meh, definitely not paying money again to see her.
Well then I guess you shouldn't go to see Britney!
what you trying to say exactly? i like xtina too but i can't really name her big hit songs except for Beautiful, I Turn To You, Genie in a Bottle, Reflection