I agree that it will be nice to follow these businesses up again, and I plan to do just that. Keep in mind though that these results are very real, at least for the short-run. They are large enough to suggest that microfinance has an important effect, for men, whether they last over time or not.
And yes, the female enterprises had about 2/3 the income of the male enterprises, but this is a fact about female enterprises in Africa in general. Also note that I did not find different results for the larger female businesses, so size alone can't be the explanation.