What's so bad about Marx?

I don't agree with everything Marx says, not by a long shot. But even the stuff that I disagree with isn't (in my humble opinion) so absurdly crazy or radical. I've read the Communist Manifesto, The Poverty of Philosophy, and some of Das Kapital, and I don't know what everyone is so up in arms about. It's hard to argue with his logic in Poverty of Philosophy and in Das Kapital the man has damn near exactly predicted the evolution of capitalism. Even the Communist Manifesto makes some great points, although its more liberal and idealist than I am. I guess my question is this; exactly what do you guys have against Marx? And I mean specifically, what policies of his do you think are absurd? At least will you admit that his ideas are not those of an extreme nut, but a rational mind who happens to be more left wing than you?