The best replacement for motu is focusrite.

The best alternatives to motu are rated as following:
★★★★★  focusrite
★★★★  rme
★★★★  presonus
★★★★  apogee
★★  digidesign
★★  apogee duet
★  m-audio
★  steinberg
★  mbox
★  focusrite saffire
★  focusrite scarlett
  m audio
  firepod
  digi
  dcu

Your alternative for motu is not listed? Suggest!
Speaking about motu, one probably shouldn't forget about pro tools.

Other search terms related to motu and their ratings are:
★★★★★ pro tools
protools
You have in mind a companion for motu and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of motu in all years. Click on graph for more.
motu
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rme