This paper proposes and evaluates an integrated method for real-time, head-tracked, 3D binaural audio with synthetic reverberation. Virtual vector base amplitude panning is used to position the sound source and spatialize outputs from a scattering delay network reverb algorithm running in parallel. A unique feature of this approach is its realization of interactive auralization using vector base amplitude panning and a scattering delay network, within acceptable levels of latency, at low computational cost. The rendering model also allows direct parameterization of room geometry and absorption characteristics. Varying levels of reverb complexity can be implemented, and these were evaluated against two distinct aspects of perceived sonic immersion. Outcomes from the evaluation provide benchmarks for how the approach could be deployed adaptively, to balance three real-time spatial audio objectives of envelopment, naturalness, and efficiency, within contrasting physical spaces