One of the best things about the PSP collection is that you can chart how things have changed from the series' inception. Although most of the early editions are largely the same (with the addition of new levels, weapons and vehicles), the series has matured quite a bit since the first game in 1996. All you need to do is play the first game and Metal Slug 6 to see how far the series has come, even on the outdated technology that is the Neo Geo. Metal Slug 6 offers 2D graphics that scale, different characters with their own unique abilities, and a difficulty mode that actually matters. These changes may not sound like much, but they add a whole new dynamic to the franchise. One can only hope that this is the direction all future Metal Slug games go; fans of the series have been waiting a long time to see some real innovation in this long-running franchise.

This is not the first time Metal Slug has made its way to a home system; we've had various incarnations of this series on everything from the PlayStation 2 to the Game Boy Advance. In fact, late last year SNK Playmore released this very compilation (unlockable bonuses and all) on the Nintendo Wii. But what sets this PSP version apart from all of the other releases is that this is the first time we've had such a comprehensive version on a handheld game system. There's no denying the appeal of playing these games on a big television, but these shooters truly make for a fantastic portable experience. It's fun to just pick these games up and play a few rounds and put it back down again, and when you're looking for something quick, fun and mindless to play on a trip or on the bus you can't go wrong with Metal Slug.

In a lot of ways Metal Slug Anthology is a better fit on the PSP than it was on the Wii, if only because the controls feel more natural on the handheld. You don't need a whole lot of buttons to play any of the Metal Slug games, so the PSP's limited buttons and lack of a second analog stick never play an issue with this compilation. When it was released on the Wii, Metal Slug Anthology offered a half dozen ways of setting up your control ... none of which felt as good as a standard game control. By contrast this PSP port only offers one way to control the action, and that's all you will need.

Unfortunately the handheld game does come with a few caveats. For instance, PSP owners will have to put up with frequent (and often lengthy) load times which can sometimes break the flow of the action. They aren't too bad, but they seem noticeably longer than other versions of the game. You will also be able to change the screen size around (offering you the ability to have it go full screen, 4:3 or original pixel), but some of these sizes look bad on the PSP's widescreen display. Neither of these complaints is that big of a deal, but they are certainly worth mentioning.

If you can put up with a few intrusive load screens then you will find yourself with the most comprehensive Metal Slug game on the planet. Fans of Contra-style 2D action games will find a lot to love in these seven titles, they are full of fantastic graphics and memorable moments. Sure there are things I would love to see added to the series (being able to shoot diagonally jumps to mind), but as a piece of software that recreates these seven games, Metal Slug Anthology does an amazing job. Don't worry that some of these games are old; the Metal Slug series is still as fun and relevant now as it was back in the mid-1990s.

SUMMARY: There are a lot of classic video game compilations already on the PSP and Metal Slug Anthology is one of the best. It offers seven of the best 2D action games of all time in one succinct package, that's a deal you shouldn't pass up ... no matter who you are!