Been watching speedruns for a while now. I know this game is a lot to bite, but just wondering if there are any differences i need to know about if im going to run the digital copy on my Vita vs the PS1 version.

Cheers

PS Vita is like the PSTV, so it will be way faster than PS1, and a bit faster than the regular PS2 with fast loading. In the run itself, there is nothing different, the changes are just from the loading speed.
Enjoy.