Though not at the start, originally I think they got on really well and would have made good friends, but by the end he had seen her on the side of a verbal attack on Buffy and I think it would have really soured his opinion of her. By the end of the season he's the only one with a reason to dislike her, she'd proven herself to the scoobies, the potentials loved her and Buffy had accepted and risen above their differences. The only one who still had a reason to dislike her by the end was Spike, who I think would still have been kinda pissed on Buffy's behalf (I know I was).

thats not the impression i got, i mean after the Scooby Gang kicked Faith out yeah sure those two had a fistful confrontation about that. But i dont think Spike hated Faith i just think the two didnt see eye to eye.

Faith pretty much reconciled with the Scoobies and made peace with the group and with Buffy, with her being much more of redemming quality about her but didnt overally radically changed her character to much.

In spikes eyes faith was the one who hurt buffy. Anyone who hurts buffy does not do well with spike

She was hitting on Buffy's boyfriend (I consider Spike her boyfriend XD) , kicked her out of her own house, never really apologized for it, never liked her since she met her, slept with her old boyfriend (Riley) and I personally think Buffy is disgusted by Faith.
Then I would pick Spike because of the points already made: She hurt buffy and anyone who does that is hated by spike