I only tested it with a 5Hz unit. I don't have a 10Hz unit, so I'm unable to comment.
A smoother map movement does look more visually appealing, at least it did at first when I tested it. Now I don't much care one way or the other. 5Hz has very little practical benefit, if any, for navigation.
Don't be too harsh on iGuidance. It is equally as good software as GMPC. It may not do anything higher than 1Hz, but it does many other things very well, and perhaps a thing or two even better than GMPC.