Overall, I see both as quite costly in terms of price per GB.
It's probably because the flash runs faster, thus having a detrimental effect on endurance, or maybe just that Phison's sales teams are not offering that sort of contract anymore with this generation. Also worth noting, last gen came with BiCS flash, the current generation of E18 SSDs all come with Micron's 96L TLC. So, it may be even farther up the chain. Though, the newer flash will be out shortly. A few E18-based SSDs with Micron's 176L TLC are in the works.
It's not a typo. It has 1.4 petabytes of endurance, equal to 1,400 terabytes. I don't think any SSD has such low endurance as 1.4TB. Even consumer SSDs from 10 years ago came with 72TB endurance ratings.
I highly suspect so, too. More so now that I received another new batch of E18 drives this week and just started testing them today. They are also exhibiting similar performance improvement from what I can tell thus far.
I still am having SLC cache measuring issues, though. Whenever I run the high QD sequential write test to these SSDs, once the SMART reports 70C, the drives pull back to that slower 1.8 GBps write speed around the 200-300GB mark. (This isn't the case when you do multiple drag and drops in real-world use in Windows. )