Can the Pegasus R4i & J2i operate without using RAID? 

Starting with the J2i, it is not configured as RAID, and configured to work as a single drive in your macOS. The J2i can only be used in RAID with the macOS disk utility.

The R4i can be configured to work as pass-thru device. You must first delete your existing array to do this, so please be aware of this. If you wish to configure in this manner please take a look at this >>Link<<

If you need further assistance please contact support.https://support.promise.com/ or call (408) 228 1400 option 4