What would you recommend for someone who a) wants to see something as small as mushroom spores, and b) would like to take decent quality pictures of them? DSLR or smartphone mount if there's one that's not super fiddly?
As for using a DSLR with the microscope, I'm guessing it might have similar issues as astronomy. When attaching the camera to the telescope (possibly same for microscope), you lose the magnification of the eye pieces. The image data is hitting the tiny tiny pixels of the DSLR so that the scale of things will be very small in your high megapixel image. This is why so many people prefer lower resolution cameras as the pixel sizes on the sensor are much larger. Just based on experience with optics, I'd imagine this would hold true to microscopes as well.
DSLRs are nice, excellent image quality, but quite expensive and heavy for the job.