And it was totally my fault!!! Dropped it one two many times and damaged the left trigger! Anyway went to buy a new one and the difference in build quality is like chalk and cheese. No more creaking and flexing side panels!! The whole controller feels solid just like the 360 controller in terms of sturdiness and I did hold s 360 controller in one hand and the new One controller in the other for a white knuckle squeeze comparison test (totally scientific!) and couldn't feel any difference at all.
So all the people who were saying the controller was designed specifically to feel that way and the flexing and creaking cost billions to design like that were talking tosh. Seems that MS have upgraded the build quality on the quiet.