Investors looking for stocks in the Insurance - Property and Casualty sector might want to consider either First American Financial (FAF) or W.R. Berkley (WRB). But which of these two stocks offers value investors a better bang for their buck right now? We'll need to take a closer look.We have found that the best way to discover great value opportunities is to pair a strong Zacks Rank with a great grade in the Value category of our Style Scores system. The proven Zacks Rank puts an emphasis on earnings estimates and estimate revisions, while our Style Scores work to identify stocks with specific traits.First American Financial and W.R. Berkley are both sporting a Zacks Rank of # 2 (Buy) right now. This system places an emphasis on companies that have seen positive earnings estimate revisions, so investors should feel comfortable knowing that these stocks have improving earnings outlooks. But this is just one factor that value investors are interested in.Value investors are also interested in a number of tried-and-true valuation metrics that help show when a company is undervalued at its current share price levels.Our Value category highlights undervalued companies by looking at a variety of key metrics, including the popular P/E ratio, as well as the P/S ratio, earnings yield, cash flow per share, and a variety of other fundamentals that have been used by value investors for years.FAF currently has a forward P/E ratio of 10.95, while WRB has a forward P/E of 22.63. We also note that FAF has a PEG ratio of 0.84. This popular metric is similar to the widely-known P/E ratio, with the difference being that the PEG ratio also takes into account the company's expected earnings growth rate. WRB currently has a PEG ratio of 2.51.Another notable valuation metric for FAF is its P/B ratio of 1.56. The P/B ratio pits a stock's market value against its book value, which is defined as total assets minus total liabilities. For comparison, WRB has a P/B of 2.07.Based on these metrics and many more, FAF holds a Value grade of A, while WRB has a Value grade of C.Both FAF and WRB are impressive stocks with solid earnings outlooks, but based on these valuation figures, we feel that FAF is the superior value option right now.Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report First American Financial Corporation (FAF): Free Stock Analysis Report W.R. Berkley Corporation (WRB): Free Stock Analysis Report To read this article on Zacks.com click here.