Riptide GP is indeed an excellent arcade racer. The game comes with three modes, twelve tracks, six vehicles and three different difficulty levels, so it'll keep you entertained for a long time. What a pity there's no multiplayer.
Reminiscent of titles such as Aqua Moto Racing or even Wave Race for the N64, Riptide GP takes the visuals to the next level, though is does so at the expense of control options, quality AI, and overall content.
Ultimately, Riptide GP is a graphically intense and fun racer that'll keep you wet, wild and fully engaged for several hours. Definitely worth $4.99, and congrats to Vector Unit on such a artistically impressive and fun effort. Now bring on the updates.