I almost replied to your other message on your printer, but I have a different Epson printer (a wide-format photo, not an all-in-one). I do use the drivers from Epson with Slackware, so perhaps what I have to say will help.
Is there a reason not to use CUPS? I can't think of any. Even if it is just you and your PC and your printer, you should use it. CUPS is easy enough to set up and requires little maintenance.
ESC/P is the "legacy" Epson printer control language. ESC/P-R is the "new generation" Epson printer control language. If both drivers are listed for your printer, then your printer will support either, but probably with different features available.
In my case, I tried both drivers with my printer. In fact I have both installed now (with different printer names, which works fine with CUPS). While both seemed OK for Libreoffice, the ESC/P-R driver would not properly scale photos from Gimp. I did not extensively test it, as photo paper and ink cost too much to waste, and the ESC/P driver works well enough for me, so I use that one. In fact, for my printer, the ESC/P driver has more options.
Use the .tar.gz or .tgz packages if available - less work than RPM.
In order get the driver to work on my Slackware system, I had to make this symlink:
# ln -s ld-linux.so.2 /lib/ld-lsb.so.3
In general this is a bad thing to do - you are 'tricking' programs into thinking your system is "LSB complaint" which it might not be, but the Epson package won't work without this link, and seems to work just fine with the link. This was true for the ESC/P driver; I'm not sure if I needed this for the ESC/P-R driver too but it doesn't hurt.
One last word: CUPS is a nasty thing to trouble-shoot. When it works, it works great, but when it doesn't work you may find yourself wading through tons of useless debug messages only to find "printer failed" with no reason. Good luck.
Hope all this helps.