I don't think any sanitiser has any affect on viruses, bacteria yes, viruses no. The same goes for antibiotics.
I don't see any inherent issue with the Dyson Hand Driers....however, all to often they are not properly/ever cleaned which over time does then look disgusting. Other more traditional models aren't really hygenic as they blow the water droplets to the floor and around the room, but people think they are cleaner because there is no accumulation on the drier itself.
Personally I hate all the paper towel waste from hand drying.....really wish Disney would set an example by eliminating paper towels for hand drying. Thousands of trash bags of waste accumulated daily just from hand drying, environmental madness.
Am I right in thinking that Universal has hand driers in just about every location? I think they still generally have paper towels available, but their usage is vastly decreased when hand driers are installed.