Digital bank SoFi Technologies (SOFI 4.24%) and online brokerage Robinhood Markets (HOOD 3.31%) both leverage their innovative platforms to disrupt the traditional financial services sector. Their strong growth rates have translated into impressive returns: Shares of SoFi are up 95% in the past year, while Robinhood stock has climbed by a remarkable 246%. After such large gains, some investors may wonder if they can keep their rallies going.Let's consider which of these fintech leaders is a better buy for y ...