I never figured out how one oil can be more cleansing than another and didn't notice any difference at all when I got rid of the castor oil. I also tried emu oil which felt weird to me too.
After some experimenting I found that I like jojoba, sunflower, safflower, and hemp seed the best. Here is a list along with how they are rated as far as being non-comedogenic and non-irritating. http://www.zerozits.com/Articles/acnedetect.htm
I just buy the least expensive but still high quality (thank you Ebay) non-comedogenic oils and mix them in a little bottle that I leave by the bathroom sink. Then I keep the big bottles in the frig. I don't know if there would be much difference if I used just 1 oil or 2 or the 3 or 4 that I usually use. I cleanse with it 2-3 times a week and also use a little bit afterwards as a night time moisturizer.