Another vote for Plusnet here. Have been with them for over 5 years so lucky to have unlimited downloads and not be on a fair usage scheme. To be fair though if you sign up to a package with one a fair usage scheme and go over the limit they do say they will thottle the speed.
Technical support is pretty good provided you to it on-line, I wouldn’t ring them unless my own BB goes down.
Also, my BB is close to being free as I have signed up quite a few people!