Quantized inertia predicts the rotation of disc galaxies simply, without dark matter and without adjustment. (McCulloch, 2012, 2017).
QI also predicts a change in galactic behaviour into the past, not predicted by any other theory which seems to be borne out by recent data (McCulloch, 2017).
The orbits of wide binaries, stars far apart that are apparently bound gravitationally but should not be, are predicted by QI (McCulloch and Lucio, 2019). Dark matter cannot be applied to these systems and MoND does not predict them.
Quantized inertia predicts that energy focused into small asymmetric or symmetric cavities can produce propellant-less thrust (McCulloch, 2018). Six labs have tested this. So far, five have shown some thrust (Perez-Diaz et al., 2021; one has not (Neunzig et al., 2021).
Spacecraft flying by the Earth for gravitational assists have shown anomalous boosts in speed. QI predicts these (McCulloch, 2008) though later flybys showed no anomaly.