Epson printers, by Apple standards are "dumb printers" in that they do not have any hardware onboard that does much interpretation of the data being sent to it. You will have to find some software that will do all of the post script interpretation on your computer and then send the bitmap out to the printer if you want true PostScript.
As I have said in other forums, if you want something, you are going to have to pay for it.
And as far as PCL is concerned, PCL isn't even a language that exists on the Mac. If you were to work in a networked printing environment, you would find that Macs speak PS to network printers and PCs speak PCL unless you force them to speak PS. With regard to reliability in network printing, PS is superior. PCL still has some weaknesses and often gets garbeled on busy networks. PS on the other hand seems to print true every time.