So, what are some good role-playing games on the iPod Touch?

Here's the situation: My mom's offered to buy me either, but if I choose the PSPgo, I must buy the case, PlayStation Network Cards, etc., while if I choose to get a iPod Touch 8GB, we agreed that she will buy me $40.00 in iTunes/App Store cards, and a protective cover/case. I can't decide which to get, so that's why I'm asking for all of your opinions on the matter. I already know the things I'll download/ buy for each, though I want games with better quality and graphics, so I'm leaning towards the PSPgo at the moment, though at the same time, if I wanted cheap games/apps, and more versatility, I know the iPod Touch beats the PSPgo in those areas. All I need to know is which one to get.