From a driver's point of view, I much prefer ILS as an approach aid - everything I need is right in front of me - much better SA. I'm no fan of PARs in general, however, RPAR is a royal pain in the arse. You can go from "Well above glideslope" to "Well below glideslope" in a matter of seconds, with a perfectly acceptable ROD on. It appears to be WAY too sensitive.
There is little point in having an instrument approach aid that has restrictions in IMC. Come the day of sh!te weather and an emergency / limited fuel, RPAR would be my LAST choice, every time.
16B