Hi Scott,
What are you using the HP-VISA library for? If you are using this to communicate with HP devices in the VXI system across the VXI bus, then you need to carry on using HP-VISA. If you are trying to use the GPIB interface on the controller then you can always try this with HP-VISA, however we would recommend that you use NI-VISA in this case.
I hope this information is helpful to you, if you have further questions please post back
Regards
Hannah
Applications Engineer
National Instruments