You know I'd never actually heard of Andy Burnham until a few months ago.
He's right to say that this is Labour's last chance. I don't think they will be (or can be) transformational enough though. Just look at the 'heavyweight economists' he's hired to help developed policy. They are all revolving-door 'economic heavyweight' types from the BoE and the OBR.
Once he is PM and it sinks in that nothing significant for normal people is going to change, I think Labour will go the same way as the Tories, and have wasted loads of time while everything goes to shit.