Do any rings ramp and shift better than the Shimano Dura-Ace rings? Not in my book
Is there a better front derailleur than the SRAM Red Yaw? Not in my book. No trimming needed ever. The combination with the Dura-Ace FH9000 is fabulous. I doubt a single bike is spec'd this way.
I am building a new rando bike. It needs cranks outside the normal length that simply not available from the big Mfgs. I am buying them from Lightning.
Factory wheels? Please.
B17 saddle. Last time I saw one of these plopped on a new bike, I had pimples and Disco dancing was the rage.
The above are a few reasons to upgrade or customize. It can cost a lot more doing it this way but eventually you have stuff you like.....bars, stems, seatposts, pedals, shoes, wheels, tires....etc.