Some users have recently had their accounts hijacked. It seems that the now defunct EVGA forums might have compromised your password there and seems many are using the same PW here. We would suggest you UPDATE YOUR PASSWORD and TURN ON 2FA for your account here to further secure it. None of the compromised accounts had 2FA turned on.
Once you have enabled 2FA, your account will be updated soon to show a badge, letting other members know that you use 2FA to protect your account. This should be beneficial for everyone that uses FSFT.
Many hardware vendors supports FreeBSD, I don't think anyone running ZFS would advice you to use Linux but oh well... There's a recent presentation about how gandi.net uses FreeBSD and their infrastructure and why they choose that OS. BSDCan2016: FreeBSD based high density filers
Napp-it is also...
Marvell controller, preferably MLC instead of TLC memory. Proven and reliable combination.
Crucial MX200, Plextor SSDs also comes to mind if you're on a budget.
At least in .eu they have quite a bit more powerful hardware at the same price as Asustor. Keep in mind that if you're going to mix HDDs sizes you can pretty much forget about redundancy in a sane manner at least.
Well, I do know that the SiL3114 are plauged with data corruption even on smaller HDDs if you use more than one channel at a time (that's a very nice design bug) . The SiL3124s aren't much better, also... it's going to be really slow and PCI isn't going to help. I'm recommending PCIe because no...
It's hackable but it's not a good idea in the long run.... Asustor (better bang for the but than Synology and QNAP in most cases) supports NTFS out of the box from what Google tells but I would recommend you switching to a native filesystem. FreeNAS has the same "issue".
Slower than the Fitlets (they are slightly more expensive) however you'll be more than fine with a MIPS or ARM box which most likely will perform better. Not to forget, warranty is a concern if you order overseas.