"For critical data, I'm now only using RAID 10"
I can't tell if you're joking or not, so no offense intended if you were.
Just in case you're not, read the links posted - RAID 10 is WORSE than RAID 5. If you lose one disk the remaining disk has to produce every single block, without error, to keep your data alive or to rebuild the RAID. If there is one single URE on the remaining disk your RAID is considered borked and you lose your weekend (at the very least). RAID 6 or Erasure Coding are the currently considered safe ways to store your important data, and even then, have a second copy somewhere. Preferably using object storage too, so you only kill one thing in a failure. It's all based on the probability of being able to recover after a disk loss, and with RAID 5 and 10 the probability is higher for a total loss of information than for recovery for a given RAID set size.
Biting the hand that feeds IT
