Around 30 minutes of A/B testing on Savage SE, which has that nice feature of box switching. Tested just on one Ownhammer IR, which I use often, so I know it. No EQs etc., just clean IR.
ReactIR switched to passive, resonance off. Torpedo sounds definitely better and fuller to me. ReactIR is too flat sounding and has quite lot of sizzle (can get rid of it by LP on 8k).
ReactIR switched to reactive, resonance on. ReactIR is much better than in passive mode. I believe it sounds a bit clearer with less sizzle (but it's still there) and the change is like applying EQ curve with more bass and more upper mids. Surprisingly, Torpedo is still excellent in comparison. It sounds middier, but with more lower mids than ReactIR. Both sound excellent, no shame for older Torpedo here. There is a difference, but it's something like 'do you like Marshall or Mesa voicing?'. Sometimes I felt like ReactIR is a bit clearer, but you know, ear is such a bastard.
Quick conclusion (based on one IR and headphones
Torpedo is still surprisingly good. Small differences can be easily managed with EQ. If I have to choose just one, it would probably be ReactIR, because it has variable attenuator, which being mostly home player I do use. I believe, Torpedo has a bit better software (even it looks awful), ReactIR has some other bells and whistles. If you are Torpedo owner and dreaming about ReactIR, stay calm and wait for a good deal.