For the last year I've researched, produced and tested ecdysterone products for my own site- gymvikingusa. Getting wholesalers to send you legit 90%+ ecdysterone is rare. But, occasionally I'll buy a company's product to test and try out. I can tell you that Double Woods is legit over 90% sterones. You can tell by the color and, of course, after distilling down and removing any plant fiber material. The only drawback is that it is in simple form. i.e. no complexing to increase bioavailability. So, you have the best purity of the mainstream market, but it's cut with a tiny percentage of rice flour- which chunks and gunks if you try to process it. To me it's like putting bad gas in a ferrari. That said, you won't find a higher purity on the mainstream market.