Hi Dan. Good question. I might be wrong, but my feeling is that linear daw ambisonic HRTF tools - especially the ambisonic convolution reverbs is of better quality than the tools like Steam and Google Resonance. Simply put - it would sound better in this situation where the goal is to adapt an existing stereo music track to an immersive environment. But given my options, it seems like you’re suggestion is the way to go. Is Unreal capable of sample accurate sync of several sound files without any drift over time?