Anyone have any trouble with eBay bought screen's touch sensitivity?

I'm on my third screen now in which the slightest bit of humidity and/or dirt makes it practically unresponsive to touch. This is something which, despite also happening with the original screen, did not occur up to even half the extent that it seems to with these screens. All of them were bought on eBay for about 10 euros each from the usual retailers from China, and all of them seemed to work quite well in the beginning. With use, though, the sensitivity always gets worse. I'm basically locking the phone all the time and cleaning it as well as my fingers to get it working properly.

I thought it could stem from from the screen unglueing from the thin plastic frame that surrounds it and the glass being at times slightly separated from the LCD(I could show a picture if this sounded unclear and anyone cares) so I tried to glue it together, but it was to no avail. Recently I've had a screen that started to have touch sensitivity problems and it was not unglueing from the frame.

It's as if these screens are simply poorly made and the digitizer is bound to fail every time. As such, I'm rather curious. Perhaps I do something wrong, or maybe there's something wrong with my phone altogether(though I really doubt it). I'm certain the ribbon's connected well as I've went through it several times, so I can't think of anything but that the screens are all faulty.

Has anyone had a bad experience with the touch sensitivity on screens bought from Chinese retailers on eBay?

I'd really appreciate some feedback on this.