I see that Atlex.com, the best place I've found to buy genuine Epson replacement ink cartridges online, is selling the R2400 ink carts for $11.20 each and you need 8 to replace a set for a total cost of $89.60. The 2200 ink carts are only $8.90 each and you only need 7 of them to replace a set for a total cost of $62.30.
Considering this, ink cost for the R2400 is 43% more expensive than for the 2200. Given that, is the quality difference worth the price? I personally have not seen any prints from the R2400 so I would appreciate hearing from those forum members out there who replaced their 2200 with the R2400.
North Wales, PA