Game is absolutely tragic.
Played it and beat 3 GP Cups after about an hour. Few things to say, the game looks absolutely disgusting compared to other racers on the GBA that have been out for ages (MKA, GT 3, even F-Zero)
The sound is absolutely dreadful, and for some reason the game is the loudest game I've ever heard on GBA so far, tunes sound like absolute rubbish and the plane sounds are even worse.
Tracks are boring and unimaginative, as you progress along the game you'll see that absolutely nothing interesting is brought in. Just the same old track layout, few corners, few speed-boosts, nothing interesting at all. Have a major quip with the fact that even flying over the slightest bit of grass at the side of the track slows you down, there isn't much margin for error in the game, you can't try and normally shave off seconds from your laptime by going across the occasional bit of grass because it WILL slow you down.
Power-ups are crap, and those rubbish little "cheats" that you get from collecting Cheato's pages such as the little creatures that you shoot to open up speed-boosts are completely pointless, namely because the speed-boosts appear in rediculous places, and EVERYONE can use them, so what's the point in spending all those cheat pages on items that'll give everyone in the race an advantage.
For a guaranteed win, pick Mumbo-Jumbo all the time, he's considerably faster than the lot... which is completely crap, sure Kazooie and Jingo (statistically) have better handling and acceleration... but what's the point when by holding R you can do massively simple turns around even the most bendy corners with any character, without it having any effect on your speed at all.
So what have I ran by so far, inbalance in characters, unimaginative tracks, annoying sounds, looks like crap, rubbish items and "cheats", oh yes... the Jiggy Challenge, which removes any actual challenge by showing you whereabouts the Jigsaw pieces are on the map. Ummmm, the fact that the game is made rediculously easy due to the completely pathetic control system, oh and just to touch on one final thing. The end stages of the GP, where you have to battle it out against the cup champion. When I say battle I mean you have to shoot the crap out of the computer character, whilst he remains hopeless using only drop-behind power-ups... then everything switches and you have to avoid his completely crap aim from behind... making these "boss" stages, a complete and utter cake-walk.
There is nothing redeeming about this game whatsoever, weigh up the amount of time this has been in "development" and compare it to the quality of the game... and I'd go as far as to say that it's the worst racer on the GBA, nay, the worst game on the GBA (being slightly worse than Rare's last release, It's Mr. Pants)
Quick Scoring :
Graphics : 3/10
Sound : 1/10
Lastability : 1/10
Gameplay : 1/10
Control : 3/10
Overall : 1/10