I'd expect Shimano stuff to be more highly engineered, and where I'd expect it to make the most difference would be chains, cogs and rings...
The top tier Sram cassettes are works of art. The old Red ones weighed nothing and were all milled from one piece, never marked your freehub etc.
@Saffronspokes started
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I'd expect Shimano stuff to be more highly engineered, and where I'd expect it to make the most difference would be chains, cogs and rings...