I'm not a big fan of Predator. I respect it's mad testosterone and kick-ass creature design, but I just never enjoyed watching it. It's a classic, make no mistake. I just don't love it.
Aliens is excellent. As much as the grunts annoy me in the film, everything else is amazing. Especially Ripley. I actually think just from pure action standpoint Predator is a superior. Plenty of explosions, running and gunning, muscular men killing everything (and getting killed)... But Aliens is more exciting, imo.
I can see Cameron fighting Cameron in the grand finale.