I had a horrible experience with Advanced Nutrients.
I've been growing for about 2 years now. Set up is two grow tents, using soil, one for flowers and one for veg. I'd previously used Foxfarm (for the first few years before that, I'd used Miracle-Gro, which was awful). Under Foxfarm, my Buba Kush plants yielded between 3/4 ounce to 2 ounces per plant. I use soil as a medium, and light the plants with two 150 watt HPS lamps per tent.
Using the 3 pack from Advanced Nutrients and set up a grow with the same clones I'd used with Foxfarm. The results were DISASTROUS. Average yield went to about a quarter ounce per plant, a 65% reduction in yield. Sincerely, I'd gotten better results with Miracle-Gro than with AN.
Upset, I emailed them to my money back. To get their alleged "100% money back guarantee," you have to call the grow line. I called the grow line, they don't offer money back at all! "get the refund from the retailer where you bought this from." I'd purchased the product two months before, and my retailer (amazon.com...not exactly a fly by night company) wouldn't honor any returns. The response from AN? "Amazon.com's not an authorized seller so we can't speak to the quality of the product you purchased."
The guy on the line then offered to send me more product. When I explained how their product had decimated my plants and how I just want my $38 back, he kept saying "yeah, I respect your decision, but we're awesome. If we suck, would we have 23 Phds? I've been doing this for years. We're great and know what we're doing. You wouldn't have heard of us if we suck." For real, the guy went on a 5 minute rant about how great AN is.
When could finally get a word in, I calmly explained how AN nutes decimated my plants and severely reduced my yields. The guy blamed my commercial soil and said "oh sure, our nutrients in commercial soil WILL CAUSE NUTRIENT LOCK and can harm your plants." Um, isn't that what Ph Perfect Technology was created to avoid? I mean, if the product is so good, why doesn't it work in any soil? Sure, switch nutes and subtle changes would be expected. But a 65% reduction in yield when I switched from Foxfarm? "Oh yeah, Foxfarm is created to soil like the stuff you'd get at Home Depot so you would get better results from them under that setting." um? Really?
To close, I asked again "So if the retailer won't honor your 100% money back guarantee?"
"oh, don't worry. They'll get your money back. Or call me and we'll give you some advice and help you out."
WOW. In just one call, Advanced Nutrients refused to honor their "100%" money back guarantee, they explained away how their product nearly killed my plants, let me know how this claim of PH Perfect Technology is a scam, and told me I'd get better results with a competitor's product.
I guess I went through this experience so you won't have to.