The new RF Explorer WSUB1G PLUS is likely the model being presented in this thread as VHF/UHF, and being compared with RF Explorer WSUB1G standard model.
If that is correct, please note the new, more advanced model has internal DSP features that, when enabled, may take a few milliseconds longer to complete a sweep by doing a better filtering of <spurs / false signals> which were not filtered by RF Explorer WSUB1G standard model.
You can still run the WSUB1G PLUS model in the same way as standard model, if you prefer, being faster: select DSP:Fast mode in the CONFIG MENU. The DSP selection allows you to switch filter / no filter spur signals so you are always in control.
More details in the DSP section of the user manual www.rf-explorer.com/manual
RF Explorer Team