Farmerkat, Those are great questions, some I would like for the companies to answer themselves. Without regulations on the market, it is difficult to get these companies to send their product for testing outside their own or associated labs - so like many others, most of my opinion is based on my own experience. The research I was able to gather outside my own experience showed me a few truths about essential oils.
1. no regulation means no consistency across companies or in labeling.
2. Essential Oils work because they are alcohols and esters containing naturally occurring chemical constituents that have (mostly) positive effects on the body.
3. Plants grown with different conditions, locations, weather factors, ect are going to produce different levels of these chemicals.
4. extraction method of essential oils is going to affect the end product.
5. The FDA usually regards EO's as a cosmetic NOT as a drug (otherwise we may see a time when you need a prescription for peppermint oil and a permit to grow it).
6. Other countries have established standards for quality - in other words minimal requirements based on an average. (
AFNOR and
ISO )
7. The bottom line governs any business, so I have found testing results showing that some products may include pure essential oils, but sometimes they are adulterated or diluted. Such adulterations are difficult to identify. Most of the time, the oils have been diluted with a carrier oil. While this is a good idea anyway because EO's are extremely strong, Do I want to pay for already diluted EO, or dilute it myself and save some storage space?
I use EO's for everything. Literally, cleaning, healthcare, illness prevention, and even just to add a nice fragrance to my home. The biggest use of EO's in my home is for pain management and mood stabilization. My Husband is medically retired from the military and is disabled from the injuries he suffered on the job. He was told after his back surgery that he would never go another day without narcotic pain meds. The meds shut his liver and kidneys down twice. We now manege his pain with EO's instead. My step Son is also mildy autistic and is prone to violent outbursts. Diffusing his favorite EO's allows him to breath in the oils - which land in his sinuses and transfer through the blood stream into his brain. Once in the brain, the right combination of EO's help him to produce calming and soothing hormones allowing him to control his outbursts.
This is literally the two situations that opened my eyes to the quality of EO's. It took a lot more of the cheaper oils to get results (if we could get results at all) than it did with the more expensive brands. I believe that I ended up using more to achieve results because of the dilution issue in the industry. In most cases it was like buying two identical bottles and one came 1/8 full of oil; 7/8 full of alcohol, and one came 100% full of EO.
My sincere recommendation in your case would be to ask both your friends for samples - try them out and choose the one that works best for you in your situation. Try the store brands too.
If you do decide to join a company for the reduced prices, learn everything you can about working the deals and stacking the discounts. On average I only pay 33% of the retail price for DoTERRA oils by working the system, and I show everyone who has joined through me how to do it too. The commissions I get from their purchases pays my 33%, so by being frugal and honest, I don't actually pay anything for all my EO's. It is saving me over $300 a month in prescription co-pays and Doctors visits on top of Whatever is left over from my commissions after I place my $100-$300 (value) Order each month.