Hi
I use UKFSN [1] & have no complaints, good speed, (just done a test and it's 
5Mbps) no connection problems & sensible caps, I currently have 30GB/month 
peak allowance and 300GB/month off-peak for £19.56 a month on a monthly 
contract, but their allowance structure will be changing soon, details on 
their website here, [2] there will no longer be an off peak allowance just 
peak allowance, anything used during off-peak won't be charged for usage.
David
[1] 
http://www.ukfsn.org/
[2] 
http://www.ukfsn.org/newadslproducts.html
-- 
FLOSS - Not just for your teeth - Free Linux Open Source Software