As of early 2008, 1DVD appear to be out of business, though we're keeping this review up for posterity.
1DVD have a cheerful, orange website which is easy to use. They list an impressive 20 genres, always good for browsing, as well as the top 100 British Film Institute movies, top 25 rentals, and a coming soon section. We'd prefer some more recommendations in different categories, but this setup isn't bad. You can search on title, director, actor, or synopsis, but we'd also prefer that the actor/directors and such were hyperlinked within the actual DVD descriptions.
Still, the descriptions do contain DVD special features info as well as a one-liner review blurb--again, more would be better, but the information is pretty good. On the customer service front, we have not heard significant criticism, and in their favour, they actually have a contact phone number. We like their padded, plain envelopes, as it isn't obvious at a glance that they contain DVDs.
Prices: 1DVD offer a 2 week free trial, but only allow 1 disc out at a time during the trial. Their prices are fairly standard for the industry, except at the 4 and 5 disc packages which are at a significant discount over others. They offer 1 disc subscription at £9.99, 2 discs at £12.99, 3 discs at £14.99, 4 discs at £16.99, and 5 discs at a very impressive £18.99. They have annual subscription rates at quite a discount; at the most common three disc level, annual is £149, essentially two months free.
If you want to cancel, you must inform them at least 5 working days before the end of the billing period, and make sure any DVDs reach them 2 days before the payment is due. If DVDs arrive after the cancellation goes into effect, you pay £1.00 per DVD per day late. Note, we have heard recent complaints about difficulty canceling free trials and getting responses to emails or even their phone line.
Design: 
Rental Basics