I had used for my 2 ESXi, and since the cards on the HCL of VMWare are I did not hesitate long -> fits all boils -> super.
As the price / performance ratio was so great I have worried for my firewall (HP N36L, ASG V8, 2 Intel Pro1000 NICs) also equal to 2.
In sum, I would have to loose 5 or 6 have these cards at home, all without running zicken.