500 ft above GS IMC is way too high to salvage the approach unless you know exactly where you are. With no glide slope you could do like my friend and break out after the airport and have to look back at where you intended to land. Quite embarassing. Sometimes it is better to swollow your pride and go around so you can do it right next time. Unless you have DME it is hard to know how close you are to the runway without the glide slope.. I found out one day going into DFW if they don't protect the ILS the glide slope doesn't mean much either. A 747 parked by the glide slope transmitter and gave us a fly down command putting us way below the real glide slope. Tower said they didn't have to protect it if it was better than 800 and 2.