The 1.2 version of NI-USRP is built off of UHD version 003.004.004. This means that if you want to use GNU Radio on a Linux box and not have to change the FW/FPGA back and forth between the two, you need to use UHD 003.004.004.
If you would like to use a newer version of UHD on Linux with GNURadio, you will need to update/change the firmware and FPGA images each time you switch which driver you are using.
Please let me know if that helps. Thannks