Just got a bit of a surprise. I ran another speedtest at Speakeasy, same New York City server.
With Web Shield enabled:
Download Speed: 2752 kbps (344 KB/sec transfer rate)
Upload Speed: 2464 kbps (308 KB/sec transfer rate)
With Web Shield paused:
Download Speed: 7145 kbps (893.1 KB/sec transfer rate)
Upload Speed: 2547 kbps (318.4 KB/sec transfer rate)
Taking out that high-density DIMM has apparently caused an increase in download speeds.