It's modelled around the suttas, but as best as is possible, they're sequential in the story they tell, and where relevant they are supported by commentary (but the commentarial additions are clearly designated as such). Its strength lies of in the use of multiple "narrator" modes... from memory, one suttanta, one Mahavihara, one something else (possibly non-sectarian historian?).
Sorry if I'm a bit sketchy, it's been a while, but to put it in context, I read this after reading the Majjhima and Samyutta Nikayas and still found much benefit from it and it would be my first port of call if there was some aspect of the Buddha's life I wanted to revisit.
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