If Warren Buffett is right that investors should be fearful when others are greedy and greedy when others are fearful, it's time to be greedy-at least with oil and gas stocks. And two big oilfield services mergers are creating perhaps the best bets. Last week, oil prices fell to less than $40 per barrel, falling further on Monday with the stock market rout. On Wednesday, West Texas Intermediate crude was trading at around $38.76, the lowest in six years. On Thursday morning, it was peaking just over $40 again. However, oil prices are still down around 60% since last summer and about 35% since mid-June. The most recent oil price slide, and subsequent gyrations, have sent a lot of investors running for cover and led industry watchers to identify companies most likely to make it through to the other side. The names could be a good entry point for an eventual recovery.