Because my TrueNAS Scale is installed on a scratch system, I will in fact scratch it now and test both (a) OpenMediaVault and (b) UnRaid. I was unpleasantly surprised to see that TrueNAS Scale's web GUI does not even provide a file browser. OpenMediaVault does. So that's where I'm headed next...
To just play with the GUI, you may install to a virtual machine (Virtual Box, or other). This is also a great way to test resiliency by removing drives or "playing" with a hex editor on one of the virtual data disks and watch ZFS work its magic of correcting on the fly.
Of course, do not commit actual, valuable, data to a VBox install, and do not expect actual performance figures.
I have not seen a file browser in OMV, and I don't know what it would be useful for. All FreeNAS "children", OMV, XigmaNAS and TrueNAS, operate on a strict segmentation: The administrator manages the NAS but does not access data; users mount shares—and browse files using whatever file browser they fancy—but do not operate the NAS.
These are far better options than Synology or QNAP at anywhere near the price. I
If it looks too good to be true, it probably is…
With this upgrade the I/O looks a bit less ludicrous (the four M.2 each have one lane of their one instead of all sharing one…).
If the ASM1166 is one of the third-party SATA controllers which do not collapse under heavy load,
if the ACQ113C NIC does behave well (that's a big "if"… last time I heard of it on the TrueNAS forum, there was an "experimental" driver for it, to be loaded by manually setting a tunable),
if everything is properly set up, with PCI pass-through of all required devices,
the whole thing looks like it could, almost, be made to work.
That's a general theme with this Storaxa project: It looks nice, but the numbers do not quite add up, technically, or economically. And a virtualised TrueNAS would still be a dangerous configuration to put into the hands of consumers.
I hope for you it is not a scam after all.