Have to second both of these. The PSP was great for RPGs, both remakes and new ones. I'll also throw in Star Ocean and Star Ocean 2, both of which were enhanced for the PSP releases. I absolutely loved Star Ocean 2 on the PS1, so getting its combat system integrated into the original Star Ocean was a dream come true. (Though I have to admit that the story kind of meanders off and goes nowhere by the end, as I recall.)There are many great RPGs on PSP. Tactics Ogre and FFT are the obvious stand outs. Atlus has some solid titles as well.
I am waiting for a killer PSN sale on PSP game so I have incentive to re-buy them digitally so I can replay them on my PS TV.