I wrote this on another forum of "which ISP". As you can see I think of them highly due to their honesty and support.
I highly recommend the Enta providers. They are a honest wholesaler/buisness ISP posting every detail of the service on their NOC.
http://noc.enta.net/
There is traffic shaping in the form of an Anti Loss Tool. This ensures there is no packet loss by bringing everyones connection down to 2Mbps in 0.5Mbps steps and then works it way up when load decreases. This only really happens at 10pm til 1-2am and on weekends (off peak). This is not used as an excuse for not adding bandwidth and can be seen by the above link. They have just installed their 4th pipe with a 5th ordered. (There has been a 400% increase in bandwidth since June so far and is set to increase at same rate.)
Enta sell to the public via various resellers UKFSN, Aquiss (who I'm with), ADSL24, Vivaciti - also resell others, Falconnet etc. They all provide great support and post regularly on the Adslguide forums (Aquiss have their own ones with few support members and owner.) along with Entanet engineers.