For my money, I'd take the kappa perfects any day. Am not a fan personally of the sound of square subs. If you want it to just be loud, by all means go with the kicker. If you want sound quality (as I'm guessing because you're box is sealed and you are going with 10's) then go with the kappas. No question. What kind of amp? I would build the box to spec for either sub specifically (rather then around 1 cube sealed as your measurement)