Since you're interested in endurance, I would recommend the Synapse. I have the alu and really like it.
You're probably eager, but it would probably serve you to give it a couple weeks to a month.
Maybe, do a road trip to different shops and try different brands.
Have fun with the discovery process.
I always recommend 105, and I've been on this forum for a while, and you just don't hear a lot of complaints about Shimano, at least at 105 or above.
I've tried SRAM and don't care for it.
Never tried Campy. It looks sexy e buono Italiano!



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