Yes I have used them in the past to tune up a BUD install at a friends house.
It wasn't really necessary, we were really just playing.
At the time all we had available was a conventional Spectrum Analyser that ya'd use in a lab. i.e. not portable or specifically designed with satellite in mind. I think what we did back then was, used a conventional DC passive Splitter to sample the IF output from the LNB. Then we made a homemade, minimal loss pad (50->75 ohms) inside a small project box, along with a cap in line to decouple the DC & prevent DC from getting to the Spec An. Input.
Was crude but it worked, and got the job done. Was probably 20 years ago, ughh
DB8E/VHF Yagi rotor FM Bandstop ap-8700 preamp 8way split LG lcd.