If we are going to rank them I believe the ranking should be as follows:
Small govt conservative Bachmann/Perry/Paul/Santorum.
Big govt conservative Gingrich.
Unknown Cain. His positions change so much and always need clarification it's really a gamble to believe he believes anything. Also, as recently as 2008 his wife voted in the Rat primaries.
Rats in Pub clothing Romney/Huntsman.
FWIW, I could vote for any of them except Romney/Huntsman & Cain I'm unsure. I'm sticking with Perry.
I have no problem with Perry.
Based on current data, he will not do well in debates with Obama.