Considered in isolation, Anytime is actually very good. It lets you try programmes you wouldn't normally watch, and there's plenty of good content to enjoy. It's worth noting that Sky will soon launch a proper on-demand service that uses the Ethernet jack on the back of the Sky+HD box to get video over the Internet.
Standard-def image quality
Sky's standard-definition image quality varies wildly. As a rule, if the channel name includes the word 'Sky', then it's a fairly safe bet the picture will look good. If the name includes the word 'ITV' followed by a number, expect the crushing disappointment of a TV picture that looks like it's travelled forward in time from the 1940s, been coloured in by a monkey with crayons, and then been made into a jigsaw puzzle by a five-year-old child with a pair of blunt scissors. This isn't Sky's fault though -- companies can lease their capacity directly from the satellite operator Astra, and opt to use less bandwidth than is optimal, which ITV does.
The good news is that the channels you really pay for, like Sky One, Sky Sports and Sky Movies all look top-dollar, even in standard definition. An upgrade to HD is always worthwhile, though, for reasons we'll explain below.
HD picture quality
We've got to take our hats off to Sky -- its HD content is the best in the UK, and represents the company's main advantage over rivals like Virgin Media and BT Vision. Because Sky makes a huge number of its own programmes, it can opt to provide them in HD. It imports those that it doesn't make itself from the US, where heaps of HD content is available. The upshot is that there are plenty of great TV shows, movies and sports programmes in HD on Sky, and they look terrific.
Sky uses 1080i as its broadcast system of choice. It's fairly generous with bandwidth for its own channels, meaning you never have to put up with a less-than-perfect picture. One of Sky's HD channels -- Sky Movies Action -- uses an entire transponder-worth of bandwidth, making for a seriously impressive picture. Whatever you're watching, though, the HD material on this box is really impressive, and we're grudgingly forced to admit that it's worth the extra £10 a month to get it.
Sound also gets a boost, with soundtracks for most movies, sport programmes and imported shows being broadcast in Dolby Digital 5.1. It's slightly annoying that not all UK-originated content, especially that on Channel 4 and ITV, is produced in proper 5.1-channel surround sound -- often it's simply a stereo feed, with Dolby Pro Logic multiplexed in. Don't worry, though -- the big shows from the BBC, like Doctor Who, have glorious 5.1-channel sound, as do imports like House and Stargate Universe.
Dolby Digital and HDMI
As with virtually every other company making set-top boxes, Sky's hardware is currently totally incapable of outputting Dolby Digital over HDMI. This means that you'll need to run either an optical or coaxial digital connector to your AV receiver to get the best-quality surround sound.
While this problem isn't a deal-breaker, it is a royal pain in the behind, and we honestly can't see why it hasn't been fixed yet. Sky says it may alter its hardware to allow for this feature in the future, but existing boxes will be stuck with the current system that requires two cables to get proper surround sound. Boo and, additionally, hiss.
Video on demand
Sky's Achilles heel comes in the form of its catch-up-TV and video-on-demand capability. It doesn't really have the ability to offer the former -- aside from material offered on the Anytime service -- but it makes a reasonable attempt at the latter. Sky's pay-per-view system has a number of dedicated movie and event channels that allow you to purchase one-off viewings.
Movies work on a rotating system, with several channels dedicated to each film. In doing this, Sky can offer what's known as a near-video-on-demand (NVoD) service. Put simply, you shouldn't have to wait more than 15 minutes for a standard-definition film to start. Less popular movies will have less frequent start times, and HD movies don't seem to have anywhere near as many showings.
We are, however, pleased to see that HD movies are charged at the same rate as their SD brethren. Taking into account Sky's monthly HD fee, we suspect charging more might end in a revolt. We'd like to see more HD selections, and we're sure this will happen with time. Expect to pay around £4 for a movie, although lower-cost deals appear from time to time.
3D available for free
If 3D is your bag, then Sky might be even more worthy of your attention. The company has already started shooting football matches in the format, and it's intending to add more and more content over the coming years. At the moment, to get access to the 3D channel, all you need to do is call the subscriber centre, and you'll be given access to it. The channel is currently free to HD subscribers but that will almost certainly change when Premier League football starts in earnest once more.