Having worked with both Delphi and Visual Basic, I've found that Delphi had the edge, especially for professional apps. Its use of Object Pascal meant you got compiled, efficient code right out of the box, and it didn't need an extra runtime like VB.
The VCL component library in Delphi is still unmatched in native code – very comprehensive built-in (and commercial) components, and customizable. Plus, Delphi's database connectivity was unparalleled and can be setup in the designer where you could see data queried and returned live in your grid component!
Delphi also supported advanced language capabilities (when compared to VB), like inline assembly and pointers, which were essential for low-level optimization or system hacking. The robust error handling in Delphi was another plus compared to VB's older 'On Error' style.
Interestingly enough, the VB6 runtime has been part of Windows for quite some time, to the point that my old VB6 projects still run fine, while my experiments with VB.NET in .NET Framework 1 and 2 currently don't, since the ringtone isn't preinstalled. (granted, moving those to modern .NET is probably fairly easy)
The VCL component library in Delphi is still unmatched in native code – very comprehensive built-in (and commercial) components, and customizable. Plus, Delphi's database connectivity was unparalleled and can be setup in the designer where you could see data queried and returned live in your grid component!
Delphi also supported advanced language capabilities (when compared to VB), like inline assembly and pointers, which were essential for low-level optimization or system hacking. The robust error handling in Delphi was another plus compared to VB's older 'On Error' style.