For my own 10G homelab network I jumped the gun and got a couple of Intel X540-T1 cards for my two servers and balked at the cost of the RJ45-SFP+ transceivers (Unifi's version is ~USD60). (I'm sure there are cheaper options for the "not hot" flavour transceivers but I didn't want to have to gamble again.)

In the end I just replaced each X540-T1 with a X520-DA2 which are pretty much the same price on eBay (under USD20) and then I can just use a DAC that's a fraction of the cost of the RJ45-SFP+ transceivers.