This ETF has shown long-term market-beating ability.For the past 10 to 15 years, growth stocks have been the driving force in the stock market. For good reason, too. Such stocks have been some of the best-performing investments.The downside is that with the growth opportunity usually comes higher risk. All stocks come with risk, but growth stocks often have more risk because their stock prices have their expectations priced into them, and investors are more likely to jump ship if these expectations aren't m ...