If you haven’t already, then you should take a look at this video of the first level of Castlevania: Dracula X Chronicles. I don’t own a PSP and it even got me excited. Try to figure that one out.
Another video that I came across was a speed run of the Boss Rush mode in Castlevania: Aria of Sorrow. GameSpot user “X_59” uploaded it, but didn’t actually play what you see. The description doesn’t list who did play the game, but the footage is still exciting nonetheless.