There are several questions surrounding U.S. refiners following their fantastic run over the past two years, but the most important one is: Can they keep it up?

On the one hand, coastal refiners like Valero (NYSE:VLO) and Phillips 66 (NYSE:PSX) have the ability to move product to both domestic and international markets, and inland refiners like HollyFrontier (NYSE:HFC) have access to cheap Canadian oil and other disadvantaged feedstocks. On the other hand, the price difference between domestic and foreign crude is getting smaller by the day, eating into margins.

Which side is right? Check out the debate between the bull -- contributor Tyler Crowe -- and the bear -- Motley Fool Energy bureau chief Joel South -- in the video below and find out whether this is still a space worthy of your investment dollars.

America's $600 billion energy problem: how you could start profiting from these three stocks today
A dark specter is looming that is ready to stop America's Energy boom right in its tracks, and no one is talking about it. This one critical element could cost us over $600 billion, but every day we wait that number grows and grows. The U.S. government thinks investment in this sector is so important, even the Internal Revenue Service will give you a free pass if you invest in this select group of stocks. Our analysts at The Motley Fool have combed over this special class of stocks and we have identified three that could make you rich! Find out the names of these IRS-gift-wrapped stocks in our special report "3 Stocks The IRS Is Begging You to Buy." Simply click here and we'll give you free access to this valuable investing resource. 

Joel South has no position in any stocks mentioned. Tyler Crowe has no position in any stocks mentioned. You can follow them on Twitter @TMFEnergy and @TylerCroweFool, respectively.

The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.