The best replacement for ultegra is dura ace.

The best alternatives to ultegra are rated as following:
★★★★★  dura ace
★★★★★  105
★★★  force
★★★  rival
★★  sram
★★  tiagra
★★  chorus
★★  dura ace chain
★  sram red
★  ultegra sl
★  sram force
★  105 cassette
★  dura ace cassette
★  105 brakes
★  dura ace di2
★  dura ace pedals
★  105 chain
★  dura ace weight
★  ultegra di2
★  105 pedals
★  sram rival
★  shimano 105
★  centaur
  veloce
  athena
  durace
  dura-ace
  105 hubs
  di2
  tiagra better
  force 22
  dura ace brakes
  campagnolo chorus
  105 bottom bracket
  105 weight
  105 groupset
  sram apex

Your alternative for ultegra is not listed? Suggest!
Speaking about ultegra, one probably shouldn't forget about bb30.

Other search terms related to ultegra and their ratings are:
★★★★★ bb30
★★★ dura ace
★★★ sram cassette
You have in mind a companion for ultegra and it is not yet here? Propose!



Google Trends

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ultegra
dura ace
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