So Hamels averages 2 more wins, negated by the fact that Latos now pitches for Cincy, who is going to help him win games. 21 K which is solid but nothing major. The ERA difference is significant, and the WHIP difference only a little bit significant.
For next season and beyond, Hamels is likely the better pitcher, but by how much isn't as clear as you guys say. I would contest that Latos would at worst maintain these differentials, with the possibility of improving on them
I'm not even going to post the numbers for Cueto and Hellickson because aside from ERA, Cueto demolishes Hellickson in every category.
For my money, I would rather have Cueto and Latos. Latos can hang with Hamels, and Cueto is miles ahead of Hellickson, and he actually had the best season of the 3 in 2012. Who's to say he won't do it again in 2013? Everyone questioned him in 2011 and he just backed it up with a Cy Young caliber 2012.
If you REALLY want to play it safe and give yourself no chance at improving, stick with Hamels. But if you want to take a small chance that would pay huge rewards, take Latos and Cueto.