Bella Vista mall and Plaza Central in Santo Domingo is where I like to shop. I don't really care too much for the different brands. I'm everywhere. Guess, Gap, El Corte Fiel. Hey, as long as I see what I like I really don't care where I buy it.
Shop online and find a reliable place to ship it.
Like the other posters said, if it not fakes then it's gonna be overpriced. There's a mall in Santiago with a Gold's Gym inside that have brand name clothes, I forget the name of the Mall.