Not only Epson Inkjets!!
Tale of woe, back in August I bought an Epson colour Laser printer and right from the beginning I got three vertical white lines on colour prints and little colour spots on B&W. Because I thought it might be easier I spoke to Epson UK Tech. Support first and they went through all sorts of things and in the end said I think that you had better have a visit from one of our Techs. Of course that was not possible so I had a go at Epson France. Very helpful, the chap went through the same things as the UK one and at the end said I'll arrange a visit from a Technician, which he did for the next day. Chap turns up checks different thingies, quite interesting to watch, he plugged his laptop, which had all the test programs on, into the printer and at the end agreed with the Support people that it was probably the photoconductor unit (its the bit at the top that does all the processing etc.). He's got one in the car, fetches it, changes it for mine, perfect. He says that you cannot have this it is my test one, and I thought he said that he would contact Epson. Wrong!!
After a couple of days I called Epson and as was subsequently proved we had a slight misunderstanding, I was told that it would take a couple of days for a replacement, I waited a week, nothing, rang back. Oh! no says the chap we cannot replace that unit you have to buy a new one it is considered to be a "consumerable" ie. like toners etc. I didn't believe him but it turns out to be true---------€238 !!!!!!!!!!!!!!!!!!!!!! At this point one's command of the French language comes to a grinding halt!!
As I continue to use it the prints are improving, in fact on some you have to look very hard to see a problem, me I have always used Epson /SEIKO products but will I continue to do so ------------------if I change I have no doubt that Canon have a trick or two up their sleeve.