Yellowed screens was a lot more than just 'some' phones and OnePlus denied it even was an issue at the start. The phone has also had extremely buggy software with 'fixes' being continually promised, but release after release problems persist. The touchscreen is probably the biggest issue. It's been plagued with issues for months upon months, with the latest 'fix' being to get the phone to ignore certain values sent to it by the sensor. Then there is their frankly appalling customer service which sends users round and round in circles and shifting as much blame away from OnePlus as possible and finding any reason they can to reject RMA requests. Even if you can get a successful RMA you're talking months from start to finish. It's not acceptable at all.
I found when I has the decide too the faux metal plastic trim dinged extremely easy and the sandstone finish rubbed off near the bottom quite quickly. Also created too when you pressed around the USB port. I was also one of the ones with the GPS that was piss poor at locking on.