Jo, if you are getting a raw deal take action.
I found this page useful when I took action against a certain virgin who dabbled in media.
http://www.thinkbroadband.com/guide/res ... oblem.htmlRefuse point blank to deal with anyone outside of the UK and do not let them fob you off with the "up to" excuse. If, for example, you have signed up for a 12 Meg line you can reasonably expect to get a substantial portion of that for most of the time, only getting 3-4 most of the time is NOT substantial, a total dropping out is unacceptable.
Record dates and times of any phone calls and an outline of what was said. Write, write and write again. Threaten to cancel any contract and do not be afraid to use the court process, but only after everything else is exhausted. Do not let them off the hook.
If the local supermarket was selling short weights you wouldn't accept it, why should an ISP be any different?