Somebody from Intel has replied to this privately to me... They said:
According to its official specification, the Intel=C2=AE SSD 730 Series currently does not support sudden power loss protection.
Check here for further reference: http://ark.intel.com/products/81039/Intel-SSD-730-Series-480GB-2_5in-SATA-6Gbs-20nm-MLC ARK | Intel=C2=AE SSD 730 Series (480GB, 2.5in SATA 6Gb/s, 20nm, MLC
However, this feature is currently supported on the Data Center SSDs such as the Intel=C2=AE SSD DC S3700 and the Intel=C2=AE SSD DC S3500 as you hav mentioned above.
I appreciate the response, but it beats me why they want to keep it secret... The static on the Internet on this subject is all completely unresolved... and very annoying.
We would like to inform you that we have received confirmation that PLI (Power Loss Imminent) is fully functional in the Intel® SSD 730 Series, and it is supported for internal SSD operations. The Intel® SSD 730 Series incorporates power loss protection circuitry, capacitors and firmware support to help protect user data.