As great as the game looks and plays, there are some issues with Prologue which simply cannot be ignored. First and most glaring, there is no damage modelling in the game. If you are moving along at 150+ mph, and you hit the retaining wall, you may lose a bit of momentum, but there won't even be a scratch in your paint-job. This is nearly inexcusable for a simulator. However it is only a prologue, which brings Gamervision to their second problem with this game: it is unforgivably sparse on features.
There are 70 cars and 6 tracks on the PS1 sounded like a lot, but for a next-gen game (without a budget price - $40), it amounts to basically a glorified demo. Since it's a racing game, there is nearly inifinite replay value, but there simply isn't enough to unlock to make it worth the full price of purchase. The added value is that you get to keep whatever cars and credits you earn once the full GT5 comes to stores, but anyone can see that $40 is a lot to ask for a demo.
