This is a paid review. I've agreed to review this site in exchange for beer money.
Homebrew 4U is a site based in England which carries homebrew kits, supplies, and also has a homebrew forum. Their main products are homebrew kits, wine kits, and cider kits. Their prices are competitive with other UK sites I checked but their site was much easier to navigate and had good descriptions for all the products. They only ship to the UK.
The Brew Buddy homebrew kits are a cool idea since they make 40 pints and you can buy refills for less than half the price of the kit. They have lager, bitter, and cider kits and refills. Note that the kit requires either a 5 gal. pressure barrel or 40 x 1 pint bottles which are both available for purchase on the site. The total cost if you go the bottle route is about 55 pounds or a little over $100 USD.
At this time, the forums look new since there is only one post which is a welcome type post. I like the forums idea for a site like this where there is high interaction with the product that naturally lends itself to discussion or questions and answers–like product support for your homebrew kit.
Instructions for the homebrew kits are available on the site which is nice in case you lose the paper copy from the box, spill half-finished beer on them, or the dog eats them. Also, they have siphoning instructions on the site to help you minimize lost beer. The whole process takes about 18-20 days.
If you are in the UK and want to give homebrewing a try or need some supplies, this looks like a nice place to shop online. The site is easy to navigate, looks professional, and has prominent links their shipping and returns policy and contact information. If you have tried them or do try them, feel free to let us know in the comments how it went.