Comodo would be my choice, they're both good but come on, as Maximus has stressed in many posts, "not having 64-bit support is just unforgivable" and should be offered.
Adding to the whole debate with how Comodo Def + handles things like Logitech drivers etc, I also agree the reason why Comodo should block something for poking its nose where it should not be. But can also understand from a end user point of view (someone who does not have a clue, complete novice) this can be kinda confusing. But one look at the forums or Userguide (maybe wrong here, sorry if I am!) should explain to them how to overcome this via trusting it etc...
Everyone has valid points, but I think Comodo is right in their approach, the complete novice user would not (as they'd see it as annoying and wonder why, without an educated viewpoint).