The thing I like about VS is its variety in sizes and styles. I think it's definitely worth it since they sell bras specifically for small-breasted women and a lot of their models are in fact quite small-breasted. Of course, it all depends on your own personal preference, though.
Victoria's Secret is ridiculously uncomfortable for me (But I'm way on the bigger breast size). If I were you I'd wear cute bralettes or not wear on at all. But if it's comfy and sexy do it :)
I am a 30 around, but have a larger cup size so I have to shop at VS. If I were you and had a flatter chest I would just embrace it... A) You don't even need to wear a bra... B) You can just wear a bralette if you really want to... but VS in your situation is not worth it
30aa is completely flat chested. Why even buy a bra? A bra is intended to support, no? No trying to be rude but if you're going to walmart to save money, might aswell save even more and go braless.