ran the speed test on my A4000/040, and found that both the XSurf-100 and mediator with 100meg PCI NIC card i have, were both pretty much level pegging at 1800-2000kb/s on both up and downloads.
I did some digging and found my old Hydranet and ariadne2 cards. worth testing?
Plusnet:- 70down/18up