You'll see I answered this in the other thread, but to repeat it here... Secure Erase is only required to restore NAND write performance on old-school drives that don't support TRIM. Both effectively do the same thing of marking previously used but no longer needed NAND blocks as free to eliminate rewrites. All modern SSD's support TRIM except in RAID arrays. Given these PCIe cards are using Sandforce SSD blades in RAID, TRIM won't work. However, even without TRIM, the garbage collection on modern SSD's is usually sufficient to maintain great performance in all but the most extreme scenarios. I think you'll be fine as long as you're not using it full-to-capacity with significant heavy writes.
BTW, It would be interesting to know if OWC has somehow managed to implement some kind of TRIM on this card, or if they have any other garbage collection beyond what SandForce provides... but I doubt it. It might be worth asking them.