RAID 5 is not a very popular RAID setup in web hosting.
Because if it provide a fault-tolerance and only use $30 of the storage available, if a disk fail, the process to restore data from the two other disk require a lot of time.
So it's a good way to not loose your data with 3 disks but it's not a solution for high-availability. So it's a RAID configuration used essentially on storage server, if you only want to make your data safe without using 50% of the storage like a RAID 1.
RAID 10 is better for web hosting (and SSD), because it provide better performance, and in case of failure, you can change a disk without having to stop your server.