We recommend the x800 and x880 printer models over the x900 and x890 for several reasons, such as: 1. the newer models seem to have more issues with clogging and flow troubles, 2. the newer models aren't as easy for the user to manually clean and maintain, 3. the newer models don't have the same cleaning functions as older models, and the ones that do have "power clean" option, it's not as "powerful" compared to previous models.
I have spoke with some x900 and x890 users who have had good results with their printers, but most have reported frequent clogging/flow issues, as well as total drop out of an entire channel. Our experience is that our 7900 needed a lot of new parts right out of the box, but has been working well since- but our 4900 died (pump and/or head?) while I was learning about it (as well as doing many other things, so I wasn't focused only on the 4900), and unfortunately was literally just a few days after the warranty expired... Many people who only ever used Epson inks contact us with clogged printers, looking for help unclogging them, as their warranty has expired (and they didn't get the extended warranty). We have helped quite a few of these people get their printers working well again with our PiezoFlush solution, but sometimes it's a strange mechanical issue or bad head that PiezoFlush can't help with. If you have or buy a x900 or x890 printer, we strongly recommend getting the extended warranty, as you will likely need it.