I believe these are just overprovisioned versions of the 1.92TB SM863, but that's just a guess.
I remember Dell doing something similar with 1.92TB Toshiba drives that actually had Toshiba's P/N for the 1.92TB version on the 1.6TB Dell version.
Here's a Cloudspeed Eco Gen. 2 for $319. The 15% coupon plus getting giftcards through a grocery store using my Amex (6% CB) put the price at $255, so $132+/TB.
SanDisk SDLF1CRR-019T-1HA1 CloudSpeed Eco Gen.II 1.92TB 2.5" SATA SSD Drive 619659137953 | eBay
If you keep an eye out, sometimes you can find the HK4E, which I believe is an over-provisioned 1.6TB version of this drive, for $300-$350.
I picked up one for my wife because her 480GB SanDisk Ultra II had trouble handling all the custom content in her sims games.
My guess is they're trying to push end of quarter volume. IME, most of the really good deals from companies tend to be near the end of a financial quarter, especially near the end of the first quarter because sales tend to drop after the holidays.
Awesome review @Patrick ! Do you have any plans to test/benchmark it when used as software defined memory?