Climbing/rappelling/caving/rescue equipment/techniques are like everything else (guns, knives, flashlight, fire starting, etc.) diverse in nature. Personal choices and “comfortability” in both equipment and techniques are often the result of “what was used to learn with”, the choice of the instructor or perhaps better, the result of personal exploration, experimentation and experience.
Just as taste and style may change with time, experimentation and experience, so does equipment and technique. No tried and true piece of equipment or technique should be totally discarded in favor of the “newest and greatest”, but used as a solid basis for judging the validly of any new item (equipment/technique) and should always be viewed as, an "add on", rather then a total replacement. That way you will have redundancy always available.
Just my 2 cents.
Pete