Although I have not disassembled the entire dashboard, I did disassemble the console, HVAC control, radio trim and removed the radio faceplate and cd player unit. I was very impressed with the robustness of the parts in general. They are all strong parts that are fastened and/or clipped together in a very sturdy manner. If the entire dashboard assembly follows the same design principles I would be fairly confident that rattles would not be an issue after reassembly. Of course, if the technician was to not assemble the dash the same way it came apart by forgetting screws or something, that's a different issue.Replacing the HVAC seems complicated... they have to remove a good part of the dashboard. I am afraid it will rattle afterwards.
Many of the parts I took out had flock tape on them where they mate to other parts, and the wire harnesses all appeared to be wrapped with either flock tape, foam, or some combination of the two. Cars I've worked on in the past have not shown such a level of detail or sturdy design with regards to plastic trim, etc.