I've had the ET2850 for more than two years. We do quite a bit of printing, but after 27 months we still haven't used up the initial filling of the ink tanks. Just in case, I bought a set of inks last month, and the cost was about half the price of a set of cartridges for the HP we used to have - cartridges that typically would last us about 9 months.
One thing to be aware of - with an HP printer, the ink jets are part of the ink cartridges, so you are replacing them every time you replace the ink cartridges. In the Epson design, the ink jets are permanent parts of the printer, and over time, they can become clogged, especially if you go a long period without printing. When I tried to print our annual Christmas letter this year, I found that the pictures in the letter came out rather badly because one of the ink jets was sputtering. There is an ink jet cleaning cycle in the software menu, and a couple of cleaning cycles solved the problem.
Works very well as a copier - just put the original on the glass, and press the button. Scanning is just as easy and scans are clean and sharp. I've only used it once for OCR, and the results were mixed - two issues. One was that the OCR output had a few errors (but the original was not very clear), and the other was in figuring out how to do OCR. Turns out that I needed to download OCR software. According to the instructions I found on line, the printer came with OCR software, but if it did, I don't know what happened to it. Doesn't matter - I found a free download that did the job.
Regarding Gadget-UK's comment about printing on card stock or heavy paper - that is a concern only if you are doing back-to-back printing. Ours works fine for one-side printing, but I agree that the fact that the paper has to go around a roller when doing two-side printing can limit the choice of papers.
So yeah - I'm happy with mine.
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