FWIW, I finally decided to just get a D-link adapter for my computer, the DWA-556 PCI-e, in part because I may eventually need the other slot that the other Netgear PCI adapter was using, but also to see if it would work any better. I got one on amazon deals (dented box, big deal) for $20, good price. It has been nothing but perfect so far, never seen a dropped connection and it always reports 300Mbps. Yes I know it may not actually always get that max throughput, but more importantly every time I do a speedtest.net test its come up the same, 35/6, which is as I as I could ever get on the other one. At odd times I'd get something like 6/2 or 3/3 or some really slow speeds on the other one, could never really tell why, but it also would drop the reported speed to 5.5/11/54/78Mbps a lot of times.
Its worth noting the that older netgear adapter never had official win7 64bit drivers, so you had to use these generic broadcom ones, which worked but are now years old.