ReadyNas 4312 Optional 10Gbe Modules

The 10GbE of the 4312X is not a user-instal;lable option for the 4312, as best I can tell.  I know it's a special mezanine card, not standard PCIe.  I also see nothing in Netgear's documentation that says there is any 10GbE option except to buy the "X" version.  However, my 4220 is equipped with an Intel X540-T2, which I have confirmed is also recognized by my older 4200V2.  It has no Netgear marking and as best as I can tell, it has no special firmware.  I don't even know if it came with it, as I purchased used.  So, I suspect that one would work just fine in the 4312.  But there appears to be only one PCIe X8 slot in a 4312, so you could only install one; and doing so would prevent later installng the SAS controller for expansion modules.

Amazon sells one with a 30 day money-back guarantee, so you could give it a shot (and let us know how it goes).  It's a bigger reward with some risk, but they sell for about half price on eBay.

We accidently purchased a 4312X and not a 4312S, so need the SFP+.

We're looking at getting a Intel X520-DA2 and installing this.

https://community.netgear.com/t5/New-ReadyNAS-Users-General/ReadyNAS-4312-Hardware-That-Works/td-p/1320952

Has anyone had issues when they've done this?

From all that I can see it should work fine.

Has performance been good? i.e. it actually runs at 10Gb?