I used to be a bit uncertain about ableton, didn't trust it as a live-tool. That was untill I actually worked with it. A friend of mine showed it to me about a year ago and I was immediatly hooked to it. It's quite a different program than other sequencers I've worked with in the past and it has definitely pushed my production forward.
Yesterday and the day before I was doing a live-act with a mate. He asked me a few weeks ago if I could help him out cause he was fed up programming his MPC. We had loads of hardware running along my laptop and it all worked perfect. It works so good that my friend is selling his AKAI to get himself a copy of Live 5.