Nothing special I'm afraid. These drives are cheaper than most because they are going to be using asynchronous NAND not the faster and more expensive synchronous NAND most others use (and sure as hell not the Toggle mode NAND the Max IOPS V3 uses). They can call it "Tier 1/Grade A" all they want, doesnt mean its fast. Just that its passed all the normal QA processes. Its still inferior NAND from a performance perspective. Their high performance model is the Mercury Extreme Pro 6G, not this drive. This drive is spec'ed and designed to compete with the "Agility 3" not the "vertex 3". Thats why its cheaper.
As for their claims of "Doesn’t Slow Down With Use Like Ordinary SSDs", unless SF has opened the firmware up just for them (doubtful) thats a load of bollocks. The commands still go through DuraClass and as such if you hammer this drive it WILL go into a lowered state....just like any SF drive. SF drives have three states: Factory Virgin, Normal operating and Hammered. No SF drive will operate in Virgin state as it would burn through the NAND faster. Like all others this one will peak and then slow down a bit and reach its normal state of performance after a few days or weeks (depending on usage). IF you continue to slam it with uncompressed data (such as CDM and AS-SSD) it will go into a hammered state to protect the NAND and stay there until the "storm" has passed. This is part of the DuraClass algorithms. If OWC is stating it wont slow down, they are either running custom firmware that will burn through the NAND much more quickly than normal as it wont go into normal state but stay in Factory state..or have removed the Hammered State...and will burn through the NAND more quickly... OR its just
PR wonkiness run amok (and they are comparing it to previous gens which slowed down even more...NOT other mfg'ers SF second gen SSDs). Guess which way I am leaning. ;)
In other words these drives are nothing special. just your average typical midgrade next gen (SF based) SSD.
EDIT:
Dont look at the sequential numbers. There will be very little difference between ANY SF gen 2 on seq read and write. Its only the 4K performance that will vary greatly. More importantly...sequential speeds are a terrible way to chose an OS drive.