Thanks to recent developments in advanced video compression techniques, it is now possible to store genuine high definition footage in surprisingly small places. The Sony HDR-CX7K offers the most memory-efficient method yet; recording all data directly to memory stick. While we've reviewed hybrid units with this feature in the past, this is the first camera we've looked at that uses memory sticks as its sole recording method. It's a curious choice that is sure to please some, but we can't help but feel that the cons outweigh the benefits.

Naturally, the main problem posed by MS technology is the limited memory it provides. As mentioned above, the new AVCHD video codec allows greater levels of compression efficiency when it comes to recording data, but this doesn't mean it will work miracles. For instance, the 4GB Memory Stick Pro Duo included in the sales package will only record 30 minutes of data in XP mode - which means you will need to frequently swap memory sticks during lengthy shoots, or be very selective with your footage.

By comparison, most high-def DVD cameras will let you record up to an hour onto a double-sided disc, while Sony's similarly priced HDR-SR7 can store over 22 hours onto its hard disk drive. We find it hard to justify a recording method that is so limited; especially when you compare the price of memory sticks to other video storage media. (i.e. - an 8GB MS Pro Duo will currently cost you around $300. While quite cheap by flash memory standards, this is obviously less cost-effective than digital tape or DVDs, which will store a similar amount of data at a pittance of the price.)

One of the main advantages of the memory stick format is the elimination of complex mechanical parts needed inside the camera to make it run - this helps to save on battery life and minimises the opportunity for hardware failures. However, it also makes the unit noticeably small and light, which is a bit of a mixed blessing. Weighing in at less than half a kilogram, the unit proves difficult to hold steady at higher zoom magnifications, producing occasionally shaky footage. With a bit of practice, this can eventually be remedied, but it still remains a factor to be wary of. On the plus side, this is one of the smallest - and cutest - cameras we have ever reviewed.

Thankfully, the HDR-CX7K makes up for these shortcomings in the one place that matters - image quality. We were just as impressed with the results of this camera as the rest of Sony's AVCHD range; with our test footage looking sharp and vibrant in a variety of settings. Once again, the inclusion of a prominently marked 'easy' button will help ensure your videos look great even if you're a first-time user. More adventurous users can explore the intuitive touch-screen interface for a host of adjustable features; including focus, white balance, shutter speeds, AE modes and digital/picture effects. Having said that, this is first and foremost a point-and-shoot camera, so don't expect the same level of freedom you would find in a professional model.

When switched to still camera mode, the CX7K is capable of capturing 6.1-megapixel images directly to memory stick. This is very impressive by handycam standards, which typically offer substandard stills which suffer from poor resolution. By contrast, the CX7K's photos are more than suitable for making glossy prints.

All up, this is a solid product capable of capturing highly impressive HD video. However, the limitations of the recording format means that frequent shooters would be better off looking elsewhere.