>I think that they have VB50 already, I don't know if they would be willing to invest in VB6
>What kind of tools improvement are in VisualInterdev/VB6 over 50 ?
>I need arguments to justify the investment.
>
>Thanks

Well, with VI you can create pages that contain code in VBScript. That code runs on the server.
With VB6, you can use WebClass to build DLLs that will run on the server. You have access to all the server's objects.

With VB5, you can create DLLs that run also on the server but it is more difficult.