I would consider AlphaMax XT, M-Test, and Kingsblood to be the top tier ones right now. All will help with libido, increasing test, sleep, mood, and cortisol control. They do have similar ingredients, but also different ingredients as well and that is what is going to make the difference for some. For example, I love forskolin for its ability to increase cAMP levels, which in turn promotes a positive change in body composition and it has an ability to increase testosterone. However, some people do not respond well to it, so if that were the case I'd suggest one of the other two products,
If you're looking for something to substantially increase testosterone levels, you would have to go hormonal or talk to a doctor. Natural anabolics do a good job, but often, I think people expect way more than they offer.