Are those brands that much different when riding the same style?
No. someone else makes the frames and assembles the parts and boxes it up , for seagoing container shipping
to the distributor that owns the brand name .. shopping price-points & types. the bikes will be more the same than different.
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then there is getting away from having a Derailleur at all .. a example of Rohloff's hub ,
done right in the 1st place , there is not much press about new and improved , so things like
adding a 36 hole hub-shell to the prior 32, and a shifter for Carbon MTB bars is about all you have ..
+ not having a big pile of cash for Advertising Buys .. driving the market .
Sram, Campag and Shimano are in a gadgeteering contest, it seems .. Using racing to show it off..