Oil prices were hit hard at the end of May, resulting in poor performance for many top oil and gas stocks. However, the market's loss could be your gain, if you use the drop as an opportunity to buy. The only question is, which stocks have the best outlook right now? For my money, you can't go wrong with ExxonMobil (NYSE: XOM), Royal Dutch Shell (NYSE: RDS-A) (NYSE: RDS-B), and Total SA (NYSE: TOT).