Everybody knows that SSDs are faster than spinning disk right? What a lot of people don't realize is that this performance increase is exponential when you have multiple editors hitting a RAID array filled with them at the same time.
So why is that?
To understand that, let's take a look at the physical side of this.
If you look at a traditional hard drive they have something called an actuator arm and a head which is a physical piece that is moving across the spindle reading the data you are trying to get from that drive.
When you have a single user reading from that hard drive its pretty simple. The data might be fragmented so that head has to move around slightly or the data is all in one spot and the head can just sit and read the data.
Once you put several of these spinning disks into a RAID set and you have multiple people trying to read from these disks at the same time that arms starts jumping around. More users equals more arms jumping around, that slows performance down.
When it comes to SSDs, the physical parts don't exist. There are no moving parts in an SSD so getting data from multiple files is not as onerous on SSDs as it is on spinning disks. This is why you'll see a bit of a performance increase if you are a single user. But once you have multiple people, hitting multiple drives, all working together at the same time that's when you'll see a huge performance increase from Hard Drives to SSDs.