Nagarjuna and the Schools

I am confused by the variety of views within Buddhism. It appears to me that Nagarjuna provides a complete philosophical justification and explanation for the Buddha's teachings and that this is accepted by many Buddhists. But not all. I'd like to ask: - Which sects or schools reject Nagarjuna's metaphysics? - On what grounds do they do so? - How do they deal with the difficulty that Nagarjuna proves all theories of Reality except his own are logically indefensible? There are three issues here: there is N's proof of the absurdity of all positive metaphysical positions (in _Fundamental Wisdom_); his 'theory of Emptiness'; the doctrine of 'Two Truths'. I wonder whether some Buddhists cherry-pick from these -- or do those who reject or accept one of them tend to reject or accept all three?