Poweredge R640 SAS SSD 12gbps

Hello, question re adding a new SSD raid1 on Poweredge R640

We currently have 4 disks on our production R640, 2 SSDs (RAID 1) - each one is SATA 6gps, 1.2TB each, for total of 1.2TB /dev/sda

we have additional 2 HDDs for extra storage (both in RAID1 as well)

we also have 4 empty disk slots in the server that I want to expand by adding another 2 SSDs in a RAID 1

because the nature of our business involves working with high volumes of market data, this means its heavy I/O with lots of disk writes during the day.

Does R640 support a 12Gbps SAS SSD configuration? I read that SAS is faster I/O than SATA, so was thinking of buying something like this, a SAS SSD

https://www.serversupply.com/SSD/SAS-12GBPS/3.84TB/DELL/92VDK.htm

any tips or suggestions for high speed, SSD disks for this server?

thank you.