This game, like Goldeneye, has an in-game timer that is visible on the screen after each level is completed. From my testing, It's also very accurate. It keeps track of your full real time over the entire level (lag, cutscenes, and fadeouts are included in the in-game time). Basically, the in-game timer keeps track of everything that happens outside of the menus. The unfortunate problem is that it also includes the loading screens after completing each level, which means that in-game time could vary between runners playing on different consoles.

At the moment, nobody else runs this game. Deciding if this game should go by Real Time or In-Game Time was tough, but I think the best decision would be to just go by real time. You'll get the fastest loading times by playing on a PS2 with fast disc speed. However, this game isn't that competitive so I would recommend just playing on whatever Playstation console you currently own.