I just got this game yesterday. IT IS THE BEST RACING GAME I'VE PLAYED IN A WHILE. I haven't unlocked anything yet. It's a nice challenge and is EXTREMELY fun to play in Multiplayer mode. Battle mode is a blast.
Mario Kart 64 was good, but Double Dash!! is just phenomenal. I was deciding whether to get F-Zero GX or MK: Double Dash!! and opted for DD!! and I
realized I made the right choice.
This game again proves that Nintendo is indeed that master of it's art. Video gaming.