IYF's expansive take on the financials has paid off over the past year. Since last April, the fund has lost less than 1.5%. XLF has dipped nearly 4% during this period. 8 Fertilizer Stocks Primed for Growth >> Investors turning to IYF pay a price. With a 0.47% expense ratio, the fund is considerably more expensive than the elder SPDR. The iShares option may be the best choice for those looking to take aim at the largest names comprising the U.S. financial sector, but when it comes to investing in small regional players, the State Street-sponsored SPDR S&P Regional Banking ETF ( KRE) trumps the iShares Dow Jones U.S. Regional Bank Index Fund ( IAT). As I explained in Monday's 5 ETFs to Watch, a massive slice of IAT's portfolio is dedicated to the super regional duo of US Bancorp and PNC Financial. Given their small size, regional banks can be inherently volatile. This risk may be magnified by the fund's substantially concentrated structure. KRE limits the size of its holdings in order to provide a more-diversified take on the regional banking industry. Even the fund's largest position, Zion's Bancorporation ( ZION), represents less than 2% of its total assets. Over time, this type of expansive approach should help to prevent investors from suffering through wild market fluctuations. Sweetening the deal, KRE is also more attractive than IAT from a cost perspective. 4 Stocks That Are Real Sleepers in 2012 >> While IYF or KRE can be turned to in order to satisfy specific financial appetites, the SPDR S&P Bank ETF ( KBE) is appropriately suited for those looking for one-stop-shop exposure. The fund is backed by a combination of Wall Street giants and regional players. Companies like Citigroup and JPMorgan do not dominate the day-to-day action, however. On the contrary, with an equally weighted strategy, each of these titans represents a portfolio slice nearly equal to that of their smaller cousins.