He was the only sane choice really. His forensic style will show up well against Boris.
Timing is good; he’s a London centric remainer who would have struggled retaking ‘the red wall’ but I suspect Brexit will be a footnote by the time Covid-19 has finished with us so he’ll be in different territory.
In truth it’ll come down to public perception of how well the Tories have dealt with Covid and the aftermath.