I'm real sick and tired of performing reverse telecine on my Canon HV20 24p tapes. Is there any real difference in quality between "real" and magic-bullet 24p from 60i stock?

Yes, shutter speed cannot be changed by MB or any other program. When you shoot at 30fps you usually have a shutter at 1/60 of a second. This creates a sharper image with less motion blur than using the shutter at 1/48 of a second, the standard speed for 24fps. Also a progressive camera will capture more details than an interlaced one. This is one of the reasons why I rather shoot at 720p than 1080i. Many times the results you get with a truly progressive, 720p, camera are more detailed.

You can always get a third party plug that will give you nice motion blur in post.
Plus you should not shoot at 30p ...but do it at 60i (though the HV20 does not have 30p anyways).