I recently went to a ballet performance with some friends after taking about 4.5 mg/kg of DXM and 3 gm of 'shrooms. I timed the doses so that I'd come up on both about 15 min into the performance.
I enjoyed it, but I would not repeat it or recommend it. Basically the shrooms accentuate the DXM high and push it further, but they are masked as well.
Coming up, it was a genuine mixture of the usual highs, but as I got into the groove it became much more odd. The colorful swirls of the dancers were very beautiful, and I enjoyed them greatly, but I also became tremendously confused. Not "hey, where am I?" confused, but existentially confused. Why do we enjoy dance? Is there a frequency domain interpretation of existence? Why is there war? Why don't we just drop everything and fuck? Why is the word "coat" the way that it is? The questions weren't quite that disjointed as they flowed through my head, they followed a logical progression, I am only trying to convey the span that they covered.
This persisted throughout the performance interspersed with occasional bouts of third plateau-like dissociation. This caught me totally by surprise, as the DXM dose I took was far smaller than my usual amount (I love 9 mg/kg even though it is too much to do more often than once in a blue moon).
As the performance finished up, I had only been tripping for about two hours, so I still was going plenty hard. I went home and did my usual DXM thing, flicking on some good music, wrapping myself in a blanket, and lying down on the floor with my face buried in pillow. I love the DXM space, and even with the lower dose I found that I could wrap myself in it. The mushrooms made the tactile much more palpable than normal, and the sensations of being cocooned in warmth were wonderful.
I stayed there for about four hours, eventually getting up and crawling into bed. Even then, I was getting superb CEVs, and it took me a while to drift off to sleep.
I think the drugs are worth more on their own though. They didn't really "synergize" in my experience, although the DXM FAQ has said some folks have had great experiences.