Yeah, I've noticed psX v1.13 has shorter loads, specially on the first one. I noticed it just after submitted the run. Since the rules only specifies the version of ePSXe emulator, I thought there was not problem on using other emulator. Also, as u said, psX is a little slower than PS2, so in case it is not available, I think it should be (considering that PS2 is also not the original platform of the game, and it has more advantage than using PS1). If ePSXe is held, I must recommend splitting any% into 3 subcategories (PS1, PS2, emulator), cause PS2 runners has a significant advantage from emulator and PS1 runners; it is no a coincidence that record holders used PS2.
However, I did this run just for fun, so there's no problem if my run is rejected. Greetings! n.n