While multiplayer is a blast, the AI in single player mode (which you must be good at in order to unlock everything) is very unforgiving, allowing a single major screw-up at best before you have no chance at finishing in the standings.
The competitors in Tube Slider are brutal and extremely difficult to beat. Racing using these controls is nigh impossible at first and takes a while to get used to, resulting in an unappetizing first course of gameplay.
Tube Slider's biggest flaw of all, though, is that it just isn't all that much fun. After your first play session with the game you'll have too strong of a "been there, done that" feeling to want to spend much more time with it.
The game can't compete with the "F-Zero"'s greater sense of speed, balance and visual finesse, and with only one gameplay mode consisting of 10 tracks that can be whipped through, it lacks the depth to keep you coming back for more.