Review (5/5): It does what I need it too, has an earthy smell, compared to the flowery french lavender.
I have been trying several brands of oils, and found that price does not equal efficacy. I did get the chance to try this brand with a sizable discount for a review.
First, I do not know enough about oils to go on about blot tests, purity etc.
This review goes only on the ease of use and smell.
First I have tried several lavenders, from the big box store one for 1/4 of the price to one that is over double this price pr fl oz.
The cheap one I tried was as expected, cheap and chemical smelling.
The expensive one has rave reviews, but is french lavender, and I found it too flowery, it actually made me sneeze. By the time I reduced the amount in the diffuse to where i don't get that problem, there was very little aroma.
Of the 3 or 4 lavender I have tried, i do like this one best in both the bath and the diffuser. Its a very earthy smell compared to the rest. and lingers long after the diffuser is turned off. the dropper is a nice addition, 3 drops in the machine lasts 2 nights. About 6 in the bath is right for me, with half a cup of epsom salts.
As I said, I do not know about oils enough to rate its grade. The 5 is based on; its worth the price and doesn't have the problems of other oils I have tried.