I bought SIG a few summers ago and have been quite impressed with both the product and the developer's responsiveness to my suggestions.

NAIC toolkit is not mac compatible, but SIG is, and there's a windows version as well. I've been able to introduce a number of our new investment club members to the SSG approach to investing without worrying about the architecture clash. We can independently run our own SSG's and compare our analyses. What used to take me half an hour is now down to a half-dozen key strokes. I spend my time thinking rather than typing and can pre-screen dozens of companies in a matter of minutes.

The NAIC keeps changing things out from under him, and yet Brad rescues his users so quickly that most probably get the upgrade notice before they know that anything is wrong.