My DD10 has moderate bilateral hearing loss. We used the reflective captioning and the handheld on our trip this last summer. She had no trouble with the reflective captioning- and didn't manage to knock it over! It was typically with the voices and was very accurate. She didn't like the handheld. Sometimes the script didn't match the voices- it was either ahead/behind or truncated. She could hear "well-enough" that she can get the pattern of the voice, so this bothered her. It probably wouldn't bother an adult- as adults could just brush it off and live with it. She HATES the head phone thingies. They don't work well (either t-coil or putting them over her hearing aids), and tend to make EVERYTHING louder- including dinosaur roars, etc. It was too hard for her to distinguish voice from background sound and the loud noises startled her (she is actually sensitive to loud sounds- probably because she hears little to nothing and then BANG!).
All in all, both Disney and Universal experiences were good for her. She got close seating in the live shows, although remember that the comedy club thingy in MK is actually live- so no captioning (we didn't realize it was "live" at the time).
We also went to Busch Gardens and they had little except sign interpreters. No reflective captioning, no handhelds, nothing! She was "too big" for the little kid rides (smallish height and age limits), but can't go on the "big" rides because she has mondini defects. She was a miserable camper, but her older sibs loved the place. We sent the teenagers and Dad back for a second day, but we went to MK instead (thank goodness for annual passes!). Her hearing is progressive, and she is learning sign, too, so that may be in her future. She was excited to "catch" the gist of some signed shows this year.
All in all, we have found our WDW and Universal experiences to be terrific.........probably better for an adult who more experienced reader and can tolerate the delays/summaries of the show rather than relying on verbatim transcripts. I say WDW does a pretty darn good job!
BTW, Talking Hands is the BEST resource on this board when it comes do dealing with hearing loss. What would we do without her?!?!