well some drum machines are actually synthesizers. You cant really get the sound of a tweakable LFO from a sampler. You really need a good combo of both. Ultrabeat in logic is a cool hybrid of both.
ya I just think what a real drummer would do. Even go take some drum lessions. Two hands two feet. Thats all he's got. Then I re-amp the drum part and I am good to go. Unless its a very electronic peace then the rules change :)