I get a theoretical 100 Mbit/s from my ISP (at least, that's how they advertise it). Using speedtest.net and my ISP's test tool I average about 800 - 900 Mbit/s. However downloads from Astraweb using sabnzbd average around 5MB/s.
Am I missing some potential download speed here or does that sound about right to you guys? (I always end up confusing myself with the bits / bytes / factor of 10 calculations...

EDIT: Just done a bit more reading and have seen people getting far higher speeds using sabnzbd, so it can obviously handle the speed.
So I see two options:
a) I'm actually maxing out my connection, and I've just calculated the MBit/s MB/s difference incorrectly (very likely).
or
b) The slowdown is coming from Astraweb.
Can anyone more knowledgeable cast any light on this?
SECOND EDIT:
By the way, I've got the cache set at 120M and have python-yenc installed as per wiki, so that should be OK.