uh? why don't they just say so in the website that it's just for mobile devices only?

maybe you should just ask them to pin point where exactly samsung service centers that they are referring to.
maybe the seller verified the ssd, making sure it's detected and working, before he sent it to you.

for used items, you will get more power on count than 9, and its total host writes will be more than 0.

oh ok i think the power on count of 9 is fine, and it's not an issue anyway. it is a new unit. how much does it cost you? if the price is right, perhaps it's one of the options for our friends here too (kc400 is a business-class ssd; good speeds; 5 years of warranty; good estimated endurance; not bad tbh)

the reason why i said power on count is ok is because my samsung xp941 was a system-pulled unit. the seller took it out from an existing system and sold it off separately; the price was cheap (at that point of time, it's just released, so the offered price was damn cheap) so i just grabbed one. when i checked its lifespan, it was left with 88%; and it has power on count that was way higher than 9 (more like a few hundred if i recalled correctly). however, after 1 year+ of usage, with many times of reformatting and clean installs, its health still remains at 88%.

if the price is right, its a good for me

one question
as im using a mITX board, if i were thinking to add in NVMe based SSD on it, its pretty much impossible as i do not have the required PCIe slot right (average mITX has 1 16x PCIe 3.0 and 4x PCIe slot only afaik)? or is there adapters to account for it?

yes, if you don't care about warranty, it's a good option. they are more affordable than retail units.

for firmware updates, you can track down machines that come with these ssds and check out their support pages for new ones (note: use it at your own risks). for samsung magician, there are plenty of tools that can be used as alternatives; with the latest version (5.x), you can just skip it, because there are so few useful functions in it, compared to previous versions.

finally the usual report from hardware.fr was out.

for ssds, the top brands with the least return rates:

1. Samsung 0,17% (previously 0,20%)
2. Intel 0,19% (previously 0,27%)
3. Crucial 0,31% (previously 0,28%)
4. Sandisk 0,31% (previously 0,62%)
5. Corsair 0,36% (previously 1,67%)
6. Kingston 0,44% (previously 0,29%)

ssds with highest return rates:
3,59% Kingston SSDNow KC400 Series 512gb
1,37% Crucial MX200 500gb
1,08% Crucial MX200 1tb
0,95% SanDisk SSD PLUS 480gb
0,93% Kingston SSDNow M.2 SATA G2 480gb

for more information, http://www.hardware.fr/articles/962-7/ssd.html

also don't forget to check out http://www.hardware.fr/articles/962-8/conclusion.html

edit: will be switching to 960 pro when i have the time to set it up. it's been in the package for too long :/