I only watched starting about 9:05. But in that time, here’s my ranking/thoughts:
Top tier:
Romney — Unfortunately, he is very good at debates. Cool, collected, presidential, and he says all the right things. Could well have won the debate.
Gingrich — when they let him speak, he usually sounds good, so long as they don’t ask him the wrong questions.
Cain — I don’t expect him win, but he comes across well when they let him speak.
OK:
Santorum — he speaks well, but always sound sanctimonious.
Perry — he doesn’t seem to do well when he’s on the defensive and has to answer 5 people all attacking him at once. Hopefully he did better in the first hour, although he didn’t screw up too badly.
Mediocre:
Bachmann — I don’t know why, because I usually like her fieryness, but tonight it just seemed grating and shrill. When she bragged about how she could actually STOP Obamacare while the others couldn’t, I unfairly kept thinking — but you were IN the house when it passed, and couldn’t stop it then.
Huntsman — he is too slick by half, and doesn’t say much I like, and his attacks while smiling are creepy.
Poor:
Ron Paul — He is always bold, and when he gets something right, he is a wonder to behold, but since his main thing I saw was explaining how we should listen to what Osama Bin Laden said, I just don’t see that as a winning strategy.
IMHO, Perry had a great first hour. And you’re right, he does not do well on defense. The frontrunner has to expect this and be prepared.