Originally Posted by
mstateglfr
In the end- yes there is trickle down technology. No, not all current generations of a lower level product are identical to the previous generation of a higher level product.
Precisely. The top of the line parts may get carbon fiber and titanium.
The middle line parts may get molded plastic covered with carbon fiber, and stainless.
The bottom of the line may get chromed (or painted) steel, and molded plastic.
Features are also frequently left out of the lower model components, such as multi-shifts.
I've found most of Shimano's bearing races (cups) tend to be good, but their cones on lower model parts are definitely second-rate.