That is a subjective question. What do you call High Quality?
Lets say you have a panorama scene of 8000x4000 pixels and this is your high quality size. It is say 4mb in size it will not display nice in a small window. Most likely it will have shimmering and have jerky panning.
In this case we'll call the small window 640x480.
You overcome this by using Tourweaver's dual size pano option. Making the first a percentage of the master high resolution panorama image. I would suggest 40% of the original meaning it will display at 3200x1600 in the small window and then load the 8000x4000 in full screen mode.
The 8000x4000 image will only ever be downloaded if called upon. Meaning the download speed to view a tour will be much faster. Until a person decides if they would like to see the scene in a higher resolution.
You can make compression adjustments for both scenes and so long as you are not "dicing" the image you can even swap out the files with those you have compressed and optimised with other software like Photoshop or Kissmyimage etc. (Remember to keep the exact file names).