I'd imagine it being more "clean" than DXM as DXM works on so many different receptors that there's a range of effects that people experience from it (a bit like how Alcohol produces a range of different experiences for different people, as that acts on lots of different receptors).
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Actually it also acts on the 5-HT3 Serotonin receptor, Nicotinic Acetylcholine receptors and the D2 Dopamine receptor.