I am flying on DFW-SCL tomorrow, and managed to snag 7A, however it appears much of the flight is empty. I think there is a high probabily I could snag 3 economy seats to make a poor man's business class. Would you recommend I keeping my premium economy reservation?

Lastly, on these airplanes, does PE get better service? or the same service as economy? I don't think AA is selling PE on this flight....they just tagged the new PE eceonomy seats as MCE.