For a fairly Conservative thinker like myself, he is far better than Christie, as their is nothing conservative about him. And Republicans tend not to win national elections when they nominate the so-called moderates like McCain and Romney who play the conservative card at the last minute to garner some support. The only people that want to see a Republican moderate lead the ticket are those that are already voting for the other candidate. I also think Rubio is far more electable in terms of personality and charisma. And sadly, politics takes into account how you look. And with Christie being morbidly obese, that will hurt his chances. I personally don't like the idea of electing Rubio as my first choice for a conservative candidate simple because much like our current President, his resume prior to joining the Senate is quite thin, and will likely show in his ability to govern. Personally I prefer to see a seasoned and experienced person that has plenty of real world experience, and is willing to challenge their own party. Rand Paul sticks out recently. I am not sure how electable he is either. My first choice is neither of the two you mention. I'd prefer to see Jim Demint run in 2016. he's battled the establishment republicans numerous times. He's actually been successful outside of gov't, and he is a whole lot more conservative than Romney or McCain.