sorry mate..
until AMD comes up with a NIC, intel is still the top performer. remember the software (aka driver) is still a big difference.
I've seen some of the home-networking tests of NICs and frankly don't agree with the testing methodology (i mean c'mon...you move a single file with FTP and base the entire performance on that!!!???). I've used 3com et al (for 10+ years mind you) and nothing compares to intel NICs in servers in terms of performance, reliability and features.
anything that has netgear in the name is not meant for serious use, this is a fact. This entire division of Bay Networks was created specifically to meet home networking needs at the lowest cost possible.
I don't want to get into a "well my netgear works great" argument. Throw 1000 transactions per second at your netgear nic and tell me what the proc is at.
BUT! after looking at your model I have to disagree with intel logic here. encryption/deenryption in hardware is all good but what exactly are you asking from a network interface card in this particular application? When you start looking at a server NIC there is a lot more you are asking of it, check out the server line.
bottom line...the network is the computer, why scrimp on that crucial link? You wouldn't buy a winmodem would you? then why buy a 10 dollar nic for a 50K server? doesn't make sense does it?