Superficially they're similar: ugly, autistic men who pretend they're trannies because they historically hate other men. Both are defined by some kind of love quest which they either undertook or are still attempting. They both have no social boundaries or really any kind of understanding of how they occur to other human beings. That's why Chris saw no problem drawing graphic furry porn in his ostensibly child-oriented comic book and why Phil has shitty, confrontational tattoos.
And of course, their childish retreats into their own little fantasy lands.
But beyond that there's key differences. The first is, for all his faults, Chris is actually a little likable. As
@AnOminous pointed out, you do kind of want to see Chris succeed at what he does because while he's clueless and closeminded he does sincerely want to have a fulfilling social life. He's an endearing figure, even if he's an ass most of the time. Most of the weird stuff Chris does is because he doesn't know any better and there's a certain charm to shit like his CWCisms and his distinct art style. Most of Chris's shitty behavior comes from naivete and piss-poor upbringing for a special needs child, rather than any malevolence.
Phil, on the other hand, is a nasty hateful little man. He doesn't want anyone's approval, just their fear and obedience. It's why he brags about carrying "weapons" around and why all his stories involve antagonizing people, real or imaginary. He sees himself as Tranny Sarah Connor, even though all he does is waddle around the west coast eating garbage and raging about cissexists on Facebook. Unlike Chris, I genuinely feel Phil is a bad person. Chris has done some nasty, awful things in his life but he's never stooped so low as to beat up his own mother.
