In reply to the rubbing/flexing.
I can be riding along with no change in gears and if I start to push hard or stand up and pedal you can get the crank to shift enough so that the chain rubs.
they tried tightening and checked it all pretty thoroughly.
Several mechanics that work in shops that sell Trek were not surprised and some were aware of that issue
It can be in any gear pretty much.
This is the FC-203 crankset....not a very high quality unit I was surprised.
I do like the gears 28-38-48

thinking about getting the Nexave FC-t410 but the gears are somewhat different I may be able to purchase other chainrings that i don't know and I will call Shimano Monday.
thank you