Anders sounds more similar to Cullen than Alistair. Because Greg Eillis voiced both Cullen and Anders.
They are a bit similar, in that they both turn to making jokes instead of answering questions. But I feel that the similarities die there.
Anders has no issues with dealing with women. He's fairly self confident, knows what he wants, and will do things to get it. He's very independent, and values his freedom above all else.
Alistair isn't half as independent as Anders is, at least not until you "harden" him. Even then, he's always thinking about the good of all people rather than himself. He's no where near as self serving as Anders is.
They both are nice enough guys, and do care about other people. So while they are similar, they are in no way the same character.
Alistair is the type who blushes if you flirt with him. Anders would be the type to attempt to say something witty, and wink suggestively.