>I have an opportunity to work with a company that uses SBT, has the source code, and modifies it extensively. Can anyone with experience modifying the SBT source code comment on their experience. I have written programs to access the SBT data before. But, I have never worked with the SBT source.

I would rather work on SBT than Visual AccountMate. Atleast SBT (although an old coding style that can be hard to read) has consistancy in the coding style. Once you have learned how they do things, it works the same through out the SBT product.

Good Luck