This information is now pretty out of date (or was) but there have been a number of strong indications that Epson decided to up the ante when it comes to third party consumables through the use of a clever firmware update system available with newer Epson printers.
The update(s) shut the doors on third party consumables that work with earlier firmware versions and effectively tie your printer into using only Epson OEM/Original cartridges.
This issue was resolved with new chip designs (v6.0) but the issue may be making a comeback as of early 2014 with reports of Epson Expression (XP) models hitting issues and some indication that other printers like the PX730WD, Artisan 837, etc.. also showing symptoms.
In short, if you don’t want to be forced to use Epson original consumables, don’t install any firmware updates
