by IanKendall » Feb 19th, '10, 09:51
The two units are very different, and a direct comparison is not really possible. Of the two, a Miller holdout is far more useful, but there are things that you can do with a Black Widow that you cannot with a gravity holdout.
If you are interested in doing kewl street trix and don't mind certain limitations on your clothing, the Black Widow may be good enough for you. If you want to perfrom more traditional miracles, go with a gravity holdout.
Take care, Ian