The model upgraded oil-and-gas explorer Devon Energy to "buy."Quarter: Devon swung to a first-quarter profit of $1.1 billion, or $2.39, from a loss of $4 billion, or $8.92, a year earlier. Revenue grew 59%. Margins turned positive. Devon holds $724 million of cash and $6.1 billion of debt, equal to a debt-to-equity ratio of 0.4. Stock: Devon has risen 12% during the past 12 months, trailing benchmarks. It sells for a price-to-projected-earnings ratio of 11 and a price-to-cash-flow ratio of 5.8, 22% and 27% discounts to industry averages. It's also cheap based on book value. Consensus: Of researchers following Devon, 16, or 59%, rate its stock "buy" and 11 rate it "hold." Benchmark Co. offers a price target of $106, leaving a potential 56% return. Goldman Sachs ( GS) believes the stock will climb 34% to $91. Visit Stockpickr's Ratings Upgrades Portfolio and Ratings Downgrades Portfolio -- Reported by Jake Lynch in Boston.