I remember reading that in a general article for oil pulling. I think it was oilpulling.com. Ever since then, I have read that there are 3 top oils recommended for pulling. In no particular order they are:
1) Sunflower Oil - For general oil pulling benefits. This is the all-around oil to use.
2) Coconut Oil - Has been known to be the hardest to pull with being how this oil can actually stay somewhat solid at room temperature. This is the oil you spit into a trash can when you're done pulling with it because IT WILL clog your pipes if you spit it out in your sink. This oil has been documented as having strong antimicrobial properties.
3) Sesame Oil - the most pleasant oil to use and has strong anti-inflammatory properties but must be refrigerated or it will go rancid very quickly.
Yes, try to get an oil that is organic, unrefined and cold pressed if possible. I like the Flora brand of oils sold in Amazon.com because they come in a glass jar for one and they have superb quality. Amazon does a great packaging job too. I already bought my second bottle of Flora Sesame Oil and it got to me in one piece once again.