You have to wonder about some of the higher dosed gear out there, but I do know some of it does work well and some of it doesn't. I don't think I would get anything that had 650mg of gear per ml. I would guess it would be severely underdosed, and if it wasn't the pain aspect wouldn't be worth it. With that said, I'm planning on running some 200/ml primo that I've eard some VERY good things about, and is supposedly smooth with low pain. So, I think (depending on the source) you can get some good quality blends and higher dosed gear that is G2G, but I'd be Leary of the ones that are overboard. If it looks to good to be true, it probably is.