short and sweet:
If you are doing several things at once that access the drives, separate spindles with the separate threads accessing the separate drives will see the most benefit from non RAID 0 drives.
If you are doing large reads/writes from a single thread, or threads that must access the same drive, then RAID 0 shows the most benefit.
And for general everyday use, do whatever want for yourself: Some like it hot, some like it cold, some like it RAIDed
For myself, RAID 10 is my fave
If you are doing several things at once that access the drives, separate spindles with the separate threads accessing the separate drives will see the most benefit from non RAID 0 drives.
If you are doing large reads/writes from a single thread, or threads that must access the same drive, then RAID 0 shows the most benefit.
And for general everyday use, do whatever want for yourself: Some like it hot, some like it cold, some like it RAIDed
For myself, RAID 10 is my fave