Based on the aggregated intelligence of 110,000 investors participating in Motley Fool CAPS, the Fool's free investing community, North America's largest oil refiner Valero Energy (NYSE:VLO) has earned a respected four-star ranking. While five-star stocks have been the best performers, our data has shown that four-star stocks still outshine the market by a significant margin and shouldn't be taken lightly; conversely, low-rated stocks have woefully lagged the market average.

With that in mind, let's take a closer look at Valero Energy's business, and see what CAPS investors are saying about the stock right now.

Valero facts

Headquarters (Founded) San Antonio, Texas (1955)

Market Cap

$18.6 billion

Industry

Oil & Gas Refining

TTM Revenue

$116.16 billion

Management

CEO William Klesse (since 2006)

CFO Michael Ciskowski (since 2003)

Return on Equity (avg. last three years, through Mar. 2008 quarter)

28.6%

CAPS members bullish on VLO also bullish on

Vale (NYSE:RIO)

Chesapeake Energy (NYSE:CHK)

General Electric (NYSE:GE)

CAPS members bearish on VLO also bearish on

Tesoro (NYSE:TSO)

ExxonMobil (NYSE:XOM)

Wachovia (NYSE:WB)

Sources: Capital IQ, a division of Standard & Poor's, and Motley Fool CAPS. TTM = trailing 12 months.

Over on CAPS, fully 1,145 of 1,176 of the All-Star members who have rated Valero -- some 97% -- believe the stock will outperform the S&P 500 going forward. These All-Star bulls include co-founding Fool David Gardner, a.k.a. TMFBreakerDave, and Hukphinn, both of whom are ranked in the top 1% of our community.

In November 2007, TMFBreakerDave informed our community that, "while there are any number of drillers these days, and operators of oil fields, what the world needs more of -- and what is a difficult (read: higher moat) business to operate in -- is the refiners."

An earlier pitch from Hukphinn in 2006 expands on that bullish line of thinking, stressing Valero's specific strengths:

[Valero] is the largest independent U.S. refiner of oil, and it has a unique capacity to process sour crude, which represents a great proportion of the new supply of oil (e.g., from Saudi Arabia and, to a much lesser but increasing extent, the Canadian oil sands). Since new refineries are not coming online anytime soon, and other refiners don't have, and are not likely to develop in the short to medium-term, the capacity to process sour crude effectively, Valero enjoys a competitive advantage that will likely benefit its shareholders for some time to come.

What do you think about Valero, especially after earnings, or any other stock for that matter? Make your voice heard on Motley Fool CAPS today. More than 110,000 investors are waiting to hear what you have to say. CAPS is 100% free, so simply click here to get started.