The best replacement for raid 10 is raid 5.

The best alternatives to raid 10 are rated as following:
★★★★★  raid 5
★★★  raid 50
★★★  raid 6
★★★  raid 1
★★★  raid 01
★★  5
★  01
★  raid 5 performance
★  raid 0
★  raid 60
★  raid 1 performance
  50
  raid 0+1
  5 performance
  zfs
  raidz2
  0 1
  shr
  1 0
  raid 5 iops
  0
  raid 1+0
  raid dp
  raid 0 1
  0+1
  1+0
  raid 6 performance
  raid 1 0
  1 performance
  6

Your alternative for raid 10 is not listed? Suggest!
Speaking about raid 10, one probably shouldn't forget about hot spare.

Other search terms related to raid 10 and their ratings are:
★★★★★ hot spare
★ 6 disks
You have in mind a companion for raid 10 and it is not yet here? Propose!



Google Trends

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raid 10
raid 5
raid 50