CSX (NYSE:CSX), the first Class 1 railroad to report its quarterly results, has turned in some classy numbers. After adjusting for last year's Katrina-related insurance benefits, operating income rose a robust 16%. Just like last quarter, volume declines were more than offset by strong pricing, reflected in roughly 7% higher revenue per unit.

The transport of agricultural commodities and export coal showed particular strength this quarter. As I discussed in a recent article on Canadian Pacific Railway (NYSE:CP), the railroads can make for a pretty interesting energy play. The rails benefit in two ways. First, there's the heightened demand for alternative fuel stocks. Up north, it's largely about the oil sands, but on the East Coast of the U.S., where CSX effectively enjoys a duopoly with Norfolk Southern (NYSE:NSC), corn and coal are the fuel stocks piling up by the carload. Rising fuel costs also affect the cost of transporting the fuel stocks themselves. This gives the rails a big leg up over the trucking industry, which gets hit much harder by a high crude price.

This freight-mover isn't afraid of an economic slowdown. Otherwise, I don't see how CSX management could justify levering up the corporate balance sheet -- i.e., taking on more debt -- to buy back 15% of shares and hike dividend payments by 25%. Nevertheless, the housing slump is taking its toll on shipment volumes. Lumber, building products, and aggregates are all being taken to the woodshed, and not in a good way. Housing pain is set to continue, and only CSX's pricing power is keeping it from experiencing a similar spanking.

Does CSX's wide moat make it a buy today? I'm having a tough time deciding. I believe that the firm will stick to its focus on yield (that revenue per unit figure I mentioned earlier), rather than competing on price to chase volume. That's pretty easy to do when your competition is limited. Still, out of the "Big Six," CSX doesn't particularly stand out to me. Competitors like Canadian National Railway (NYSE:CNI) and Burlington Northern Santa Fe (NYSE:BNI) have equally solid margins, and can be purchased at comparable or lower multiples to cash flow and earnings.

Investors here should train their thoughts on one key question: whether the apparently high quality of CSX's management merits its small share-price premium.

Further Foolishness at full steam:

Fool contributor Toby Shute doesn't own model trains or shares in any company mentioned. The Motley Fool conducts itself according to the following disclosure policy.