The few sets I've seen done on Ableton have really bored me to tears.
It takes the art of performance away. Sure, you still need to know what your doing, how to put a good set together etc but it's just really boring.

I wanna see/hear the DJ manipulate the vinyl and show me his technical skill.
I wanna hear a record start to driftout and have to be nudged back. Ableton just don't sound the same.

It's probably perfect for surgeon 'cos it suits his style perfectly (i.e. dull) .
But for someone like James Ruskin to use it? Come on man and pull yer self together and do it proper!!!