Primo all day. I've run it for a long time with continual blood work, with literally zero numbers out of range. I do realize this will vary from person to person. I personally sent the primo out to be analyzed, so I know it was real as well.
It keeps my dry, full and vascular. Most noticeably, it jacks my metabolism up more than any other compound. The only negative I've noticed is sometimes my hair can shed, but I'm prone to that genetically anyway.