If there's anything the recenthas highlighted, it's that you should spend a bit of time thinking about the company you choose to get you online.
If you have aspirations of doing a lot of downloading, there are ISPs that are happy to let you, but you'll need to be prepared to pay a little bit more. No matter how 'unlimited' low-cost providers claim to be, there will always be a caveat of some sort. Usually, this will be in the form of a contended connection -- that's when there are a lot of people essentially fighting over the same lump of bandwidth. Or it might be that certain kinds of traffic are restricted, such as P2P -- BitTorrent and iPlayer both use P2P technologies.
The key to a good ISP, in my opinion, is one that sets its pricing at a sensible level. So if you want a good, fast service, don't just go with the cheap one. Look for companies that are honest in what they are offering. There are a few gems out there -- UKFSN for example offers a number of packages, one of which will fit your usage.
Local loop unbundling (LLU) companies also have an advantage because they don't use BT's network. An LLU ISP installs its own equipment in the telephone exchange. It will still use your BT phone line, but it will provide the link between the exchange and the Internet. This keeps congestion to a minimum because you aren't sharing connections with every other ISP. Be offers up to 24Mb broadband for £24 -- there are no restrictions and they haven't moaned about iPlayer yet.
The only downside to LLU ISPs is that each exchange must be fitted with your ISP's equipment. The good news is you can check this online by entering your phone number and postcode.