very hard question for me cause i love each one for a different reason.
predaking=the most "cohesive" predatory unit as a whole.
devs= pure brutality
superion=....ok...not as much love for sups.
abominus=a strong combined form,needing a self timer for them to seperate.
computron=the "techno" aspect of them with the futuristic designs appeal to me.
defensor=one of my very first "complete" combiners as a young lad.
bruticus=simply bad@ss in a giant decepticon package.
menasor=psychotic gestalt.nuff said.
but to choose one........
i choose predaking overall for toy size,character developement,combined mode,etc.