I purchased this card a while back and it works! Since I only used it for connecting to the Internet, I never really had a chance to push it to the limit in terms of bandwidth performance. I did notice negligibly better pings over the onboard ethernet I was using, but they were within range enough that I don't believe it was the card itself, so much as good timing.
It works fine, has tons of potential configuration options, but if you're not doing anything particularly special with it, I doubt it'd be worth the cost over an onboard NIC.
10/100/1000 Mbps auto-negotiation
PCI-E x1 network card with low-profile adapter
Configure a custom computer with the Intel Gigabit CT PCI-E Network Adapter.