Powerful four-mana haste creatures have been Standard staples in as many formats as I can remember. Cards like Skizzik, Giant Solifuge, Hellrider, and even Bloodbraid Elf have served as powerful haymaker creatures high in the curve of aggressive red decks, and Dust Stalker is going to fill that role in Standard this fall. With five power, Dust Stalker attacks into Siege Rhino, so it has the potential to be one of the finer creatures in Battle for Zendikar.
Playing Dust Stalker alongside other colorless creatures will get the most mileage from it. The more aggressive colorless creatures are printed, the better this will become, and early spoilers indicate there are going to be plenty of constructed-playable options. Keep in mind, the drawback can even be turned into an advantage that protects against sorcery speed removal spells like Ruinous Path. The Eldrazi tribal type is also sure to lead to some excellent synergies.
I am not keen on picking up Dust Stalker anywhere near its current presale price of around $5, but that price might actually be a reasonable price down the road if some very efficient colorless creature that cost less than four mana are printed. If it does not catch on immediately in Standard, I would look to pick these up cheap this fall, because Oath of the Gatewatch is likely provide more colorless creature options to fill a supporting role.