For a dashboard upgrade supposedly aimed at attracting the 'casual' audience, New Xbox Experience actually has a lot of love for the core 360 enthusiast gamer. The Party mode craved by Live users has been incorporated, tweaks long asked for have been made to the VGA/HDMI video outputs, but perhaps most surprisingly of all, Microsoft has allowed gamers to optionally install their games to hard disk. This is - potentially - a very good thing.

Eurogamer has never been a massive fan of the mandatory installations required on many PlayStation 3 releases. It has a fundamental impact on the 'plug and play' nature of console gaming, especially when you can be sitting about for up to 25 minutes waiting to play your brand new release. It also forces you to manage hard disk space efficiently, especially if you have a lower-capacity drive in your PS3. There's also the fact that once you've deleted your game install, as you inevitably will in order to get more mandatory installs onto your hard disk, you'll need to wait another 25 minutes if, for example, you fancy a one-off late-night blast on Devil May Cry 4 sometime in the future.

That said, we've always been fan of the optional installs found in PS3 games like Ridge Racer 7, Virtua Fighter 5, and more recently, Disney's excellent Pure. You've still got that instant accessibility that is a fundamental part of console gaming, but if you want your games to load faster, and you're willing to deal with the hassles of deleting content to let your new games run, the option is there. With NXE, remarkably, that option is available for every single game in your library - except Crackdown or Dead or Alive Xtreme 2, which bizarrely aren't compatible with the new hard disk function.

NXE launches on 19th November. But will HDD sales go into overdrive on the 20th?

The only other PS3 comparison worth mentioning is the question of install and deletion times. The 360 stores its files as disc images - whatever the Xbox version of an ISO may be. It's literally one file. That means that installation times are basically the same for any given amount of data, and deletion is virtually instant (as just one file is being erased from the table of contents). PS3 on the other hand uses variable installation techniques depending on the developer - the reason Devil May Cry 4 takes so long to install is that it's copying across multiple files rather than just one sustained write. It's also why it takes a long while to delete too.

But the real question for 360 owners is: just how much of an impact does the optional install make? With so many games streaming data from the DVD on the fly, do we actually see any improvements to gameplay as well as loading times? Do all games benefit with shorter loading times? We set out to find out.

The methodology for the tests was remarkably straightforward - my workhorse Xbox 360 Elite ran a carefully selected range of ten top games, first from DVD, then from hard disk. Video captures of both gameplay run-throughs allowed us to get frame-accurate loading times (rounded up to the nearest half-second) and the comparison of the selected footage could also be used to judge any differences in game performance.

As the vast majority of the userbase would be running NXE from the 20GB hard disk, that's what we did too. In truth, I've never got around to moving my content over from the launch era hard disk to the 120GB drive that came with the Elite. This aged drive has never been formatted and never had its cache cleared. It's basically had three years of everyday heavy use, and for the purposes of this test, we left just 7GB free - in short, we're filling the hard disk to capacity, just to make things even more challenging.

As the opportunity to install to HDD is obviously a compelling argument for upgrading the hard disk (and probably a key reason for adding the feature in the first place) we also did some tests on the default 120GB drive, unused and unloved since I bought the Elite, but perhaps now worth a bit more respect.

Enough small talk. Let's get to work.