My assumption has been that 16:9 mode would be better than "cropped 4:3" because you're not "throwing anything away." (The one drawback I have found is the distorted picture in the camera. Tthough a 16:9 monitor shows a perfect picture, it doesn't help the camera operator...) 
My camera having 16:9 guides in 4:3 mode - combined with the fact that Spot & his associates never sleep and have given us Ultimate S - makes me wonder which is the best way to go. 
If you convert 4:3 to 16:9 and play it on a 16:9 TV, are you "zooming in?" Is there a noticeable loss of quality? 
Just wondering what others think or may have experienced.
Kevin