i've asked this question before but i feel the need to ask it again.

I've never thought he was evil. From the start, he's never been on anyone's side, he's on his own side.
He just doesn't care about people he doesn't care about.

He's what's known as an antihero.
"In fiction, an antihero is generally considered to be a protagonist whose character is contrary to that of the archetypal hero, yet typically retains many heroic qualities. Some consider the word's meaning to be sufficiently broad as to additionally encompass an antagonist who, in contrast to the archetypal villain, elicits considerable sympathy or admiration." (link)

He's neither a hero or a villain.
He doesn't have the obvious "Justice for all!" motives, but he doesn't have the "Everyone must suffer!" attitude either.

I don't think he's evil. I don't think he really has a side, he just goes with whichever side benefits him more at the time.

I think that's the thing about this show, the villians aren't exactly 1 dimensional characters who can be catergorizied as good or bad all of the time. They're more 'grey' characters so to speak. Some things they do are clearly wrong on all levels, while other things they do are a bit more questionable due to their intentions.

With Mr. Gold it's all about power. He'll do anything that's to his advantage. He will even play both sides at the same time to get what he wants. He lost his son, because he would not give up his power.
Regina knew that her mother manipulated Snow. I am waiting to find out what Regina did to her mother. Since her mother did not appear to be around when she was queen. Only her father was shown.
Regina, like Mr. Gold, looks out for her own best interest. I think it's because thier natures are so simular that they repell each other.
So, I think they are both evil now, but maybe not beyond the possibility of resemption.