The touch is lag and not responsible like my old 2 years Lumia 520. It's annoying all the time especially when unlocking the phone with PIN. I have to touch (push) the screen to make it work.
.... and also the phone acts weird sometimes.
Hey guys! My friend bought 535 two days ago and he was also complaining about the touch lag and responsiveness, and I found out that the screen magnifier was turned on, after turning off the screen magnifier the touch was very smooth and responsive. Try this out if it can help you. It would be better to try this option out other than replacing the handset. You can turn off the screen magnifier(settings->ease of access->screen magnifier).
Please post your feedback, so it can help other people as well.