MX vs. ATV Unleashed was released on home consoles last year and now it's more or less arrived on the PSP in the shape of MX vs. ATV: On the Edge. While the name is different, the game features many of the tracks and vehicles from the console game, but hasn't been tailored enough to really feel like a handheld gaming experience. Even so, extreme sports fans looking for an alternative to the pretty poor ATV Offroad Fury: Blazin' Trails on the PSP should find plenty to enjoy.

As with Unleashed, the focus of the game is MX bikes and ATVs, although you can race a number of other vehicles once those race series are unlocked. They're unlocked by using points you've earned from pulling tricks during races, but given that many of the alternative vehicles feature some pretty wacky control, the incentive to blow your points on these race series isn't great. The bikes and ATVs are the best vehicles in the game, but they also suffer from some rather sensitive controls.

If you've played Unleashed you'll know that steering is a little twitchy, especially if you're new to this kind of game, but on the PSP it'll take an extra amount of time to get used to things. Even Unleashed veterans will find it all too easy to over steer into corners and end up off the track numerous times in each race. You'll come good in the end, but the initial learning curve is rather steep. The pre-load jump system from Unleashed is included, and learning when to use this is vital to achieving fast lap times, with awkward landings on the peak or upward slope of a mound almost always causing you to unwillingly leave your vehicle.

In what seems to be the norm for MX and ATV games, the indoor arenas simply aren't as much fun to race as the hilly outdoor courses. The indoor arenas lack the huge jumps and impressive views seen when racing outdoors, and they all tend to look the same. With the number of riders cut down to four in this PSP game, compared to six in Unleashed, the indoor races are even more dull than usual, but at least there are less competitors to land on your head while you're minding your own business - an event that almost always results in you coming out worst.

Once you've adjusted to the extremely sensitive controls, On the Edge seems extremely comparable to its home console brother, but it's lacking a Championship mode. Every race is a one-off, with no real sense of progression: once a race is complete you can either retry or go back to the main menu. With the painful load times that plague On the Edge, navigating around menus after every race soon becomes rather tedious, and makes the omission of a Championship mode all the more confusing. Four-player local wireless support and a number of single-player game modes mean there's plenty to do, but the game simply feels incomplete without a structured single-player career mode.

The outdoor courses far outclass the indoor arenas

Unleashed was no stunner, but it did the job, and the same applies to On the Edge. For a PSP game the draw distance on the outdoor courses is impressive and the fairly stable frame rate is nice to see. The soundtrack does the job without ever really trying, with the likes of the Black Eyed Peas and Papa Roach being perfectly adequate for the game, and engine sounds recreate the rather whiny sound of these vehicles perfectly well. Other than the sound of your rider being thrown from his vehicle for the umpteenth time, there's really little else going on in the sound department.

Racing bikes and ATVs in real life is about as niche as sports get, and the same applies to the video games. The sensitive controls are a huge hurdle that needs to be crossed for newcomers, but existing fans of THQ's extreme sports series will soon ease into a competent handheld game. The lack of focus in the single-player game is disappointing, but with limited options for extreme sports fans looking for a PSP game, On the Edge will fit the bill nicely.