I think that most of the premium defense rounds all act about the same since they are all trying to meet the FBI standards. I would then say that if they meet these standards they WILL act similar. There will be some differences between brands. If we assume the end result to be similar (within the test standards) then the other factors need to be considered. Things such as reliability, recoil, availability,........ If you or your gun, which is just a machine, doesn't like a particular type of ammunition you shouldn't use it. If you find a few loads that meet "the standard" and are reliable then look to which loads meet your preferences. You may want deep penetration or lots of expansion with shallow penetration. This is where YOU must decide what you think is the best.
I just read "Duty Calls" by Richard Mann in the Dec. 2012 Shooting Illustrated about the new Critical Duty ammo. (<---Cya legal stuff there). Basically Mann says that the Critical Defense/Duty lines are evolutions of the XTP bullets. The designs of the two lines were meant to achieve different balances between penetration, recoil, and expansion. The C. Duty leans more toward penetration and barriers while the C. Defense is concerned more with recoil and expansion. It is a good article about the two loads.
When picking a defense load the FBI standards are a nice place to start. Then you must find out what your gun does/doesn't like. Then pick a load that meets you needs regarding recoil, penetration, expansion...... Just my$.02