Rainbow manufacturer - Rexair Inc. makes 13 kinds of fragrances:
Assorted, Aroma Therapy, Gardenia, Vanilla, Mulberry, Violet, Orange, Apple Blossom, Spice,Siberian Pine, Lemon, Rose fragrances and Deodorizer a.k.a. D&A.
Deodorizer comes in a large 32 ounce bottle. The rest of them are sets of 4 a bit under 2 oz bottles. Bottles have a cap and a cork with a small hole that allows you to dispense small amount of the fragrance into your RainMate or vacuum cleaner basin/container.
We have had people who were very happy with original fragrances and they would not order anything else but genuine fragrances. Other customers insisted that aftermarket fragrances were way better and more concentrated than the Rainbow scents. So this is really matter of a personal perception. If you have had never bought any of the Rainbow scents I would suggest give it a try and order 1 set of assorted original scents and a bottle of your favorite scent in aftermarket. Pick 1 bottle of each brand of aftermarket scent and see which one you like the most. Then once you decide on the manufacturer you favor the most - then "splurge" and spend more money on fragrances.
Buying online usually saves you money on tax (if you are not in the same state as the seller) but will get you for shipping. Shipping on fragrances tend to be relatively high because it is a liquid and it is heavy. However if you spend a certain amount, majority of sellers would offer you free shipping. Keep in mind that "Free Shipping" is NOT a bottom line. What matters is the grand total and reliability of the seller.