I produce with Ableton but I DJ with usbs on CDJs.
Ableton as a DAW is phenomenal, but for performing live I think I would have to really sit down and learn the software inside out, along with the controller functions to go with it (like the AKAI APC40) before being comfortable to perform live on it.
Would be interesting to see if we could get some tutorials posted on here.
RE: Live DJ'ing with Ableton