Just a heads up before someone does a run for PSP, the game isn't actually available on PSN to download (same with Time Busters - https://www.speedrun.com/bbttb)

The only way to get either game on a PSP is to mod the system, which wouldn't be legit or fair to PS runners.

FYI PSP has REALLY fast load times for most PS1 games (much faster than PS2s FDS).