are "compatible" printer inks worth it?

Generally, I would say yes. However, if you have very high-end needs, or an expensive printer (there's probably a tiny risk to the printer), it might not be worth it. All compatible cartridges are probably not created equal, so I would look for reviews. For standard text-printing on a cheapo inkjet, like your epson, I would give it a try. Maybe someone else can recommend a good ink cartridge knockoff brand. I used one in college for my epson and it was fine.

You can also see this semi-related question: http://www.fluther.com/ld/851/

I have used re-manufactured color ink cartridges from Inkjetsuperstore. I had one cartridge that had a non-working blue; they replaced it free when I called and complained. I don't know that these cartridges print quite as much as regular cartridges, but for a cost of $14.99 each as opposed to $35.00 each, I continue to use them if I have a LOT of color printing to do.

The cheapies have been good to me