I have the exact same Epson Stylus SX535WD (six months old), and alongside it my previous DX6050 (so about five years old). They both run fine on cheap compatible inks. However, when using the cheap inks, they are more prone to blockage if not used for a couple of weeks.

There are two easy answers. The more expensive is to run "Posh" Epson inks through every second or third change of cartridge. The second, which is much cheaper, is to simply print one sheet every few days. I print off a work diary on the DX6050 once a week, and that is enough for tip-top printing the rest of the time. If I don't do this, it does block up, and I have to run the darn head-cleaning utility, which rarely works well. Just make sure the sheet has a little mix of each colour, so all cartridges are used.

I do think the compatible cartridges deteriorate in the machine faster than Epson ones - Epson cartridges seem OK after a few months of light use, but compatibles are drier and less functional.

From the compatible price you are paying, you are still paying much more than I do - I get THESE, which work out at £15 for 2 sets, plus a couple of extra black. I can't say how they last in the 535, as the first set is in (and working), but I bought these for the 6050 for all those years, and it is fine.

I also used THIS SUPPLIER for the DX6050, but not yet for the 535

I use the high yield Stag cartridges in my SX535WD. They seem to have a reasonable life.

bjh - I'm not heavy colour print user and have not found any drying out with the Stag cartridges. I can go quite a few days without any colour printing. I use a monochrome laser for the majority of my printing.