As a newly minted IFR pilot my first approach in IMC weather was to CYXX. I was in a PA34 and was vectored to final between the IF and the FAF ( outer marker ) for the ILS. The approach has no DME so I did not know exactly how far back I was but rapidly became suspicious because I was quickly approaching the glide path check altitude with the glide slope needle still full down. I went around at the check altitude with the needle still full down, diverted to better weather and did a LOC only approach. The radio shop subequently confirmed the glide slope had failed with a permanent full down indication and no flags. ( and yes I checked it on the ground before takeoff ). THAT needless to say made me a big believer in Glide path check altitudes
On a seperate topic I will not allow an approach to be changed after established on the LOC/in bound track ( in IMC ) on any airplane I am in, Therefore the practice of timing the FAF to MAP segment is a waste of time. If the glide path fails I/we would immediately start a missed appoach, make sure nothing else is wrong and then rebrief the approach we are now going to fly. Changing the approach type from the one briefed and the one you are mentally up to speed inside the outer marker strikes me as introducing too much risk for the small time saving gained.